patch 9.2.0413: Scrolling wrong with 'splitkeep' when changing 'cmdheight'

Problem:  Cursor is not adjusted when 'cmdheight' is changed to cover
          the cursor with 'splitkeep' ~= "cursor".
Solution: Handle window resize for 'splitkeep' after changing 'cmdheight'.
          Ensure previous window height is set when changing 'splitkeep'
          (Luuk van Baal).

closes: #20043

Signed-off-by: Luuk van Baal <luukvbaal@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

runtime/doc/builtin.txt

@@ -1,4 +1,4 @@
-*builtin.txt*	For Vim version 9.2.  Last change: 2026 Apr 27
+*builtin.txt*	For Vim version 9.2.  Last change: 2026 Apr 28
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -705,6 +705,8 @@ tabpagebuflist([{arg}])		List	list of buffer numbers in tab page
 tabpagenr([{arg}])		Number	number of current or last tab page
 tabpagewinnr({tabarg} [, {arg}])
 				Number	number of current window in tab page
+tabpanel_getinfo()		Dict	get current state of the tabpanel
+tabpanel_scroll({n} [, {opts}])	Bool	scroll the tabpanel
 tagfiles()			List	tags files used
 taglist({expr} [, {filename}])	List	list of tags matching {expr}
 tan({expr})			Float	tangent of {expr}
@@ -11884,6 +11886,38 @@ tabpagewinnr({tabarg} [, {arg}])			*tabpagewinnr()*
 		Return type: |Number|
 
 
+tabpanel_getinfo()					*tabpanel_getinfo()*
+		Return a |Dictionary| describing the current state of the
+		tabpanel (see |tabpanel|).  The dictionary has these keys:
+			align		"left" or "right"
+			columns		width in screen columns
+			scrollbar	|TRUE| if a scrollbar is shown
+			offset		current scroll offset in rows
+			total		total number of rows rendered
+			max_offset	largest valid value for "offset"
+
+		The "total" and "max_offset" values are only accurate after
+		the tabpanel has been drawn at least once.
+
+		Return type: dict<any>
+
+
+tabpanel_scroll({n} [, {opts}])				*tabpanel_scroll()*
+		Scroll the tabpanel by {n} rows.  Positive values scroll down
+		(later tabs become visible), negative values scroll up.  The
+		new offset is clamped to the valid range.
+
+		When {opts} is a |Dictionary| and its "absolute" entry is
+		|TRUE|, {n} is used as the new absolute scroll offset
+		instead of a delta.
+
+		Returns |TRUE| if the scroll offset changed, |FALSE|
+		otherwise (for example when the tabpanel is not shown, or
+		the offset is already at the requested value).
+
+		Return type: |vim9-boolean|
+
+
 tagfiles()						*tagfiles()*
 		Returns a |List| with the file names used to search for tags
 		for the current buffer.  This is the 'tags' option expanded.

runtime/doc/channel.txt

@@ -1,4 +1,4 @@
-*channel.txt*	For Vim version 9.2.  Last change: 2026 Apr 15
+*channel.txt*	For Vim version 9.2.  Last change: 2026 Apr 28
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar

runtime/doc/options.txt

@@ -1,4 +1,4 @@
-*options.txt*	For Vim version 9.2.  Last change: 2026 Apr 21
+*options.txt*	For Vim version 9.2.  Last change: 2026 Apr 28
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -9052,41 +9052,22 @@ A jump table for the options with a short description can be found at |Q_op|.
 	Optional settings for the |tabpanel|,  It can consist of the following
 	items.  Items must be separated by a comma.
 
-		align:{text}	Specifies the position of the tabpanel.
-				Currently supported positions are:
-
-				left	left-side
+	    align:{text}    Specifies the position of the tabpanel.
+			    Currently supported positions are:
+				left	left-side  (default)
 				right	right-side
-
-				(default "left")
-
-		columns:{n}	Number of columns of the tabpanel.
-				If this value is 0 or less than 'columns', the
-				tab panel will not be displayed.
-				(default 20)
-
-		scroll		Enable mouse wheel scrolling over the tabpanel
-				area when the tab list exceeds the visible
-				screen height.  The scroll step is controlled
-				by 'mousescroll'.  When disabled (the default),
-				the tabpanel shows the page containing the
-				current tab, with no way to view tabs outside
-				that page.
-
-		scrollbar	Reserve a one-column scrollbar in the tabpanel
-				showing the current scroll position.  The
-				scrollbar uses the |hl-PmenuSbar| and
-				|hl-PmenuThumb| highlight groups for the track
-				and thumb respectively.  Clicking on the
-				scrollbar column jumps the thumb to that
-				position; the thumb can also be dragged.
-				Implies "scroll".
-
-		vert		Use a vertical separator for tabpanel.
-				The vertical separator character is taken from
-				"tpl_vert" in 'fillchars'.
-				(default off)
-
+	    columns:{n}	    Number of columns of the tabpanel.  (default 20)
+			    If this value is 0 or less than 'columns', the
+			    tabpanel will not be displayed.
+	    scrollbar	    A one-column scrollbar is always displayed at the
+			    right edge of the tabpanel, regardless of the
+			    "align:" setting.  (default off)
+			    See |tabpanel-scroll|.
+	    vert	    The vertical separator is drawn at the boundary
+			    between the tabpanel and the buffer area.
+			    (default off)
+			    The character to be drawn uses "tpl_vert" from
+			    'fillchars'.
 	Examples: >
 		:set tabpanelopt=columns:16,align:right
 		:set tabpanelopt=

runtime/doc/syntax.txt

@@ -1,4 +1,4 @@
-*syntax.txt*	For Vim version 9.2.  Last change: 2026 Apr 23
+*syntax.txt*	For Vim version 9.2.  Last change: 2026 Apr 27
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -6155,7 +6155,8 @@ TitleBarNC	Title bar for inactive Gui's window.
 Visual		Visual mode selection.
 							*hl-VisualNOS*
 VisualNOS	Visual mode selection when vim is "Not Owning the Selection".
-		Only X11 Gui's |gui-x11| and |xterm-clipboard| supports this.
+		Only X11 Gui's |gui-x11|, |xterm-clipboard| and |wayland-selections|
+		supports this.
 							*hl-WarningMsg*
 WarningMsg	Warning messages.
 							*hl-WildMenu*

runtime/doc/tabpage.txt

@@ -1,4 +1,4 @@
-*tabpage.txt*	For Vim version 9.2.  Last change: 2026 Apr 26
+*tabpage.txt*	For Vim version 9.2.  Last change: 2026 Apr 28
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -482,42 +482,37 @@ The vertical separator character is taken from "tpl_vert" in 'fillchars'.
 You can customize the appearance of the tab page labels using the highlight
 groups: |hl-TabPanel| |hl-TabPanelSel| |hl-TabPanelFill|
 
-SCROLLING IN THE TABPANEL:				*tabpanel-scroll*
+SCROLLING IN THE TABPANEL				*tabpanel-scroll*
 
 When the total height of the tab page list exceeds the visible screen height,
-the tabpanel by default displays the "page" that contains the current tab page
-and offers no way to view tab pages outside that page.
+mouse wheel events over the tabpanel area scroll the tab page list up or down.
+The scroll step follows the 'mousescroll' setting.  Wheel events inside the
+tabpanel area are consumed by the tabpanel and do not trigger
+|<ScrollWheelUp>| or |<ScrollWheelDown>| mappings.
 
-To make the tabpanel scrollable, add "scroll" to 'tabpanelopt': >
-	:set tabpanelopt+=scroll
+The current tab page is always brought into view: when the selected tab page
+changes (by |gt|, |gT|, |:tabnext| etc.), the panel scrolls so the current
+entry is visible.
 
-With "scroll" enabled, mouse wheel events over the tabpanel area scroll the
-tab page list up or down.  The scroll step follows the 'mousescroll' setting.
-Wheel events inside the tabpanel area are consumed by the tabpanel and do not
-trigger |<ScrollWheelUp>| or |<ScrollWheelDown>| mappings.
-
-To additionally show a vertical scrollbar indicating the current scroll
-position, use "scrollbar": >
+To show a vertical scrollbar indicating the current scroll position, add
+"scrollbar" to 'tabpanelopt': >
 	:set tabpanelopt+=scrollbar
 
-The "scrollbar" value implies "scroll".  A one-column scrollbar is reserved at
-the edge of the tabpanel; clicking on the scrollbar column moves the thumb to
-the click position, and the thumb can be dragged to scroll continuously.
-
-When "vert" is combined with "scrollbar", the scrollbar is drawn next to the
-vertical separator, on the panel side.
+A one-column scrollbar is always displayed at the right edge of the tabpanel,
+regardless of the "align:" setting in 'tabpanelopt'.  Clicking on the
+scrollbar column moves the thumb to the click position, and the thumb can be
+dragged to scroll continuously.
 
 The scrollbar uses the |hl-PmenuSbar| highlight group for the track and
 |hl-PmenuThumb| for the thumb.
 
-The scroll offset is remembered across redraws but is reset when "scroll" or
-"scrollbar" is toggled off and back on.
+The scroll offset is remembered across redraws.
 
-MOUSE CLICKS IN THE TABPANEL:				*tabpanel-mouse*
+MOUSE CLICKS IN THE TABPANEL				*tabpanel-mouse*
 
 A left click on a row in the tabpanel selects the tab page that the row
-belongs to.  Unlike the tabline, a double click in the tabpanel does not
-open a new, empty tab page; it is treated the same as a single click.
+belongs to.  Unlike the tabline, a double click in the tabpanel does not open
+a new, empty tab page; it is treated the same as a single click.
 
 For finer-grained control, the 'tabpanel' value may contain |stl-%[FuncName]|
 click regions.  Clicks on those regions are dispatched to the callback

runtime/doc/tags

@@ -10896,6 +10896,8 @@ tabpagewinnr()	builtin.txt	/*tabpagewinnr()*
 tabpanel	tabpage.txt	/*tabpanel*
 tabpanel-mouse	tabpage.txt	/*tabpanel-mouse*
 tabpanel-scroll	tabpage.txt	/*tabpanel-scroll*
+tabpanel_getinfo()	builtin.txt	/*tabpanel_getinfo()*
+tabpanel_scroll()	builtin.txt	/*tabpanel_scroll()*
 tag	tagsrch.txt	/*tag*
 tag-!	tagsrch.txt	/*tag-!*
 tag-binary-search	tagsrch.txt	/*tag-binary-search*

runtime/doc/terminal.txt

@@ -965,6 +965,20 @@ term_start({cmd} [, {options}])			*term_start()*
 		input and one output handle, with no separate handle for
 		stderr.
 
+		Note: term_start() always uses RAW mode for its callbacks.
+		"out_cb" and "err_cb" receive the raw chunk of data as read
+		from the OS.  A single callback invocation may contain
+		multiple lines separated by NL, and (for stdout via a pty)
+		each line may have a trailing CR from the line discipline
+		(ONLCR).  If per-line handling is desired, the callback must
+		split "msg" on NL and strip the trailing CR itself.
+		Example: >
+			func Handle(ch, msg)
+			  for line in split(a:msg, "\n")
+			    echom substitute(line, '\r$', '', '')
+			  endfor
+			endfunc
+<
 		There are extra options:
 		   "term_name"	     name to use for the buffer name, instead
 				     of the command name.

runtime/doc/usr_41.txt

@@ -1,4 +1,4 @@
-*usr_41.txt*	For Vim version 9.2.  Last change: 2026 Feb 16
+*usr_41.txt*	For Vim version 9.2.  Last change: 2026 Apr 28
 
 
 		     VIM USER MANUAL	by Bram Moolenaar
@@ -1081,6 +1081,8 @@ Buffers, windows and the argument list:
 	tabpagebuflist()	return List of buffers in a tab page
 	tabpagenr()		get the number of a tab page
 	tabpagewinnr()		like winnr() for a specified tab page
+	tabpanel_getinfo()	get current state of the tabpanel
+	tabpanel_scroll()	scroll the tabpanel
 	winnr()			get the window number for the current window
 	bufwinid()		get the window ID of a specific buffer
 	bufwinnr()		get the window number of a specific buffer

runtime/doc/version9.txt

@@ -1,4 +1,4 @@
-*version9.txt*	For Vim version 9.2.  Last change: 2026 Apr 26
+*version9.txt*	For Vim version 9.2.  Last change: 2026 Apr 28
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -52616,8 +52616,8 @@ Other ~
 - Allow mouse clickable regions in the 'statusline', 'tabline' and the
   'tabpanel' using the |stl-%[FuncName]| atom.
 - Enable reflow support in the |:terminal|.
-- Added "scroll" and "scrollbar" sub-options to 'tabpanelopt' so the tabpanel
-  can scroll when the tab page list exceeds the visible screen height.
+- Enabled scrolling for the tabpanel when the tab page list exceeds the screen
+  height.  Also added the "scrollbar" sub-option to 'tabpanelopt'.
 
 Platform specific ~
 -----------------
@@ -52651,6 +52651,8 @@ Various syntax, indent and other plugins were added.
 Functions: ~
 
 |ch_listen()|		listen on {address}
+|tabpanel_getinfo()|	get current state of the |tabpanel|
+|tabpanel_scroll()|	scroll the |tabpanel|
 
 Autocommands: ~
 

runtime/syntax/vim.vim

@@ -2,7 +2,7 @@
 " Language:	   Vim script
 " Maintainer:	   Hirohito Higashi <h.east.727 ATMARK gmail.com>
 "	   Doug Kearns <dougkearns@gmail.com>
-" Last Change:	   2026 Apr 20
+" Last Change:	   2026 Apr 28
 " Former Maintainer: Charles E. Campbell
 
 " DO NOT CHANGE DIRECTLY.
@@ -159,9 +159,9 @@ syn keyword vimFuncName contained getbufline getbufoneline getbufvar getcellpixe
 syn keyword vimFuncName contained histget histnr hlID hlexists hlget hlset hostname iconv id indent index indexof input inputdialog inputlist inputrestore inputsave inputsecret insert instanceof interrupt invert isabsolutepath isdirectory isinf islocked isnan items job_getchannel job_info job_setoptions job_start job_status job_stop join js_decode js_encode json_decode json_encode keys keytrans len libcall libcallnr line line2byte lispindent list2blob list2str list2tuple listener_add listener_flush listener_remove localtime log log10 luaeval map maparg mapcheck maplist mapnew mapset match matchadd matchaddpos matcharg matchbufline matchdelete matchend matchfuzzy matchfuzzypos matchlist matchstr matchstrlist matchstrpos max menu_info min mkdir mode mzeval nextnonblank
 syn keyword vimFuncName contained ngettext nr2char or pathshorten perleval popup_atcursor popup_beval popup_clear popup_close popup_create popup_dialog popup_filter_menu popup_filter_yesno popup_findecho popup_findinfo popup_findpreview popup_getoptions popup_getpos popup_hide popup_list popup_locate popup_menu popup_move popup_notification popup_setbuf popup_setoptions popup_settext popup_show pow preinserted prevnonblank printf prompt_getprompt prompt_setcallback prompt_setinterrupt prompt_setprompt prop_add prop_add_list prop_clear prop_find prop_list prop_remove prop_type_add prop_type_change prop_type_delete prop_type_get prop_type_list pum_getpos pumvisible py3eval pyeval pyxeval rand range readblob readdir readdirex readfile redraw_listener_add redraw_listener_remove
 syn keyword vimFuncName contained reduce reg_executing reg_recording reltime reltimefloat reltimestr remote_expr remote_foreground remote_peek remote_read remote_send remote_startserver remove rename repeat resolve reverse round rubyeval screenattr screenchar screenchars screencol screenpos screenrow screenstring search searchcount searchdecl searchpair searchpairpos searchpos server2client serverlist setbufline setbufvar setcellwidths setcharpos setcharsearch setcmdline setcmdpos setcursorcharpos setenv setfperm setline setloclist setmatches setpos setqflist setreg settabvar settabwinvar settagstack setwinvar sha256 shellescape shiftwidth sign_define sign_getdefined sign_getplaced sign_jump sign_place sign_placelist sign_undefine sign_unplace sign_unplacelist
-syn keyword vimFuncName contained simplify sin sinh slice sort sound_clear sound_playevent sound_playfile sound_stop soundfold spellbadword spellsuggest split sqrt srand state str2blob str2float str2list str2nr strcharlen strcharpart strchars strdisplaywidth strftime strgetchar stridx string strlen strpart strptime strridx strtrans strutf16len strwidth submatch substitute swapfilelist swapinfo swapname synID synIDattr synIDtrans synconcealed synstack system systemlist tabpagebuflist tabpagenr tabpagewinnr tagfiles taglist tan tanh tempname term_dumpdiff term_dumpload term_dumpwrite term_getaltscreen term_getansicolors term_getattr term_getcursor term_getjob term_getline term_getscrolled term_getsize term_getstatus term_gettitle term_gettty term_list term_scrape
-syn keyword vimFuncName contained term_sendkeys term_setansicolors term_setapi term_setkill term_setrestore term_setsize term_start term_wait terminalprops test_alloc_fail test_autochdir test_feedinput test_garbagecollect_now test_garbagecollect_soon test_getvalue test_gui_event test_ignore_error test_mswin_event test_null_blob test_null_channel test_null_dict test_null_function test_null_job test_null_list test_null_partial test_null_string test_null_tuple test_option_not_set test_override test_refcount test_setmouse test_settime test_srand_seed test_unknown test_void timer_info timer_pause timer_start timer_stop timer_stopall tolower toupper tr trim trunc tuple2list type typename undofile undotree uniq uri_decode uri_encode utf16idx values virtcol virtcol2col
-syn keyword vimFuncName contained visualmode wildmenumode wildtrigger win_execute win_findbuf win_getid win_gettype win_gotoid win_id2tabwin win_id2win win_move_separator win_move_statusline win_screenpos win_splitmove winbufnr wincol windowsversion winheight winlayout winline winnr winrestcmd winrestview winsaveview winwidth wordcount writefile xor
+syn keyword vimFuncName contained simplify sin sinh slice sort sound_clear sound_playevent sound_playfile sound_stop soundfold spellbadword spellsuggest split sqrt srand state str2blob str2float str2list str2nr strcharlen strcharpart strchars strdisplaywidth strftime strgetchar stridx string strlen strpart strptime strridx strtrans strutf16len strwidth submatch substitute swapfilelist swapinfo swapname synID synIDattr synIDtrans synconcealed synstack system systemlist tabpagebuflist tabpagenr tabpagewinnr tabpanel_getinfo tabpanel_scroll tagfiles taglist tan tanh tempname term_dumpdiff term_dumpload term_dumpwrite term_getaltscreen term_getansicolors term_getattr term_getcursor term_getjob term_getline term_getscrolled term_getsize term_getstatus term_gettitle
+syn keyword vimFuncName contained term_gettty term_list term_scrape term_sendkeys term_setansicolors term_setapi term_setkill term_setrestore term_setsize term_start term_wait terminalprops test_alloc_fail test_autochdir test_feedinput test_garbagecollect_now test_garbagecollect_soon test_getvalue test_gui_event test_ignore_error test_mswin_event test_null_blob test_null_channel test_null_dict test_null_function test_null_job test_null_list test_null_partial test_null_string test_null_tuple test_option_not_set test_override test_refcount test_setmouse test_settime test_srand_seed test_unknown test_void timer_info timer_pause timer_start timer_stop timer_stopall tolower toupper tr trim trunc tuple2list type typename undofile undotree uniq uri_decode uri_encode
+syn keyword vimFuncName contained utf16idx values virtcol virtcol2col visualmode wildmenumode wildtrigger win_execute win_findbuf win_getid win_gettype win_gotoid win_id2tabwin win_id2win win_move_separator win_move_statusline win_screenpos win_splitmove winbufnr wincol windowsversion winheight winlayout winline winnr winrestcmd winrestview winsaveview winwidth wordcount writefile xor
 
 " Predefined variable names {{{2
 " GEN_SYN_VIM: vimVarName, START_STR='syn keyword vimVimVarName contained', END_STR=''

src/channel.c

@@ -3510,46 +3510,7 @@ may_invoke_callback(channel_T *channel, ch_part_T part)
 		// invoke the channel callback
 		ch_log(channel, "Invoking channel callback %s",
 						    (char *)callback->cb_name);
-#ifdef FEAT_TERMINAL
-		// For a terminal job in RAW mode (term_start()), split msg on
-		// NL and invoke the callback once per line with trailing CR
-		// stripped.  This ensures out_cb/err_cb receive one line at a
-		// time regardless of how much data arrives in a single read.
-		if (ch_mode == CH_MODE_RAW && msg != NULL
-			&& channel->ch_job != NULL
-			&& channel->ch_job->jv_tty_out != NULL)
-		{
-		    char_u *cp = msg;
-		    char_u *nl;
-
-		    while ((nl = vim_strchr(cp, NL)) != NULL)
-		    {
-			long_u len = (long_u)(nl - cp);
-
-			if (len > 0 && cp[len - 1] == CAR)
-			    --len;
-			argv[1].vval.v_string = vim_strnsave(cp, len);
-			if (argv[1].vval.v_string != NULL)
-			    invoke_callback(channel, callback, argv);
-			vim_free(argv[1].vval.v_string);
-			cp = nl + 1;
-		    }
-		    if (*cp != NUL)
-		    {
-			long_u len = STRLEN(cp);
-
-			if (len > 0 && cp[len - 1] == CAR)
-			    --len;
-			argv[1].vval.v_string = vim_strnsave(cp, len);
-			if (argv[1].vval.v_string != NULL)
-			    invoke_callback(channel, callback, argv);
-			vim_free(argv[1].vval.v_string);
-		    }
-		    argv[1].vval.v_string = msg;
-		}
-		else
-#endif
-		    invoke_callback(channel, callback, argv);
+		invoke_callback(channel, callback, argv);
 	    }
 	}
     }

src/cmdexpand.c

@@ -4771,7 +4771,7 @@ copy_substring_from_pos(pos_T *start, pos_T *end, char_u **match,
     segment_len = is_single_line ? (end->col - start->col)
 			: (int)(ml_get_len(start->lnum) - start->col);
     if (ga_grow(&ga, segment_len + 2) != OK)
-	return FAIL;
+	goto fail;
 
     ga_concat_len(&ga, start_ptr, segment_len);
     if (!is_single_line)
@@ -4806,13 +4806,13 @@ copy_substring_from_pos(pos_T *start, pos_T *end, char_u **match,
     word_end = find_word_end(end_line + end->col);
     segment_len = (int)(word_end - end_line);
     if (ga_grow(&ga, segment_len) != OK)
-	return FAIL;
+	goto fail;
     ga_concat_len(&ga, end_line + (is_single_line ? end->col : 0),
 	    segment_len - (is_single_line ? end->col : 0));
 
     // Null-terminate
     if (ga_grow(&ga, 1) != OK)
-	return FAIL;
+	goto fail;
     ga_append(&ga, NUL);
 
     *match = (char_u *)ga.ga_data;
@@ -4820,6 +4820,10 @@ copy_substring_from_pos(pos_T *start, pos_T *end, char_u **match,
     match_end->col = segment_len;
 
     return OK;
+
+fail:
+    ga_clear(&ga);
+    return FAIL;
 }
 
 /*

src/drawline.c

@@ -1464,12 +1464,11 @@ win_line(
 	    {
 		area_highlighting = TRUE;
 		vi_attr = HL_ATTR(HLF_V);
-#if defined(FEAT_CLIPBOARD) && defined(FEAT_X11)
-		if (X_DISPLAY &&
-			((clip_star.available && !clip_star.owned
+#if defined(FEAT_CLIPBOARD) && (defined(FEAT_X11) || defined(FEAT_WAYLAND_CLIPBOARD))
+		if ((clip_star.available && !clip_star.owned
 						    && clip_isautosel_star())
-			    || (clip_plus.available && !clip_plus.owned
-						    && clip_isautosel_plus())))
+			|| (clip_plus.available && !clip_plus.owned
+						    && clip_isautosel_plus()))
 		    vi_attr = HL_ATTR(HLF_VNC);
 #endif
 	    }

src/edit.c

@@ -1132,6 +1132,10 @@ doESCkey:
 	case K_COMMAND:		    // <Cmd>command<CR>
 	case K_SCRIPT_COMMAND:	    // <ScriptCmd>command<CR>
 	    {
+		bufref_T    save_curbuf;
+		varnumber_T tick = CHANGEDTICK(curbuf);
+
+		set_bufref(&save_curbuf, curbuf);
 		do_cmdkey_command(c, 0);
 
 #ifdef FEAT_TERMINAL
@@ -1139,10 +1143,15 @@ doESCkey:
 		    // Started a terminal that gets the input, exit Insert mode.
 		    goto doESCkey;
 #endif
-		if (curbuf->b_u_synced)
-		    // The command caused undo to be synced.  Need to save the
-		    // line for undo before inserting the next char.
+		if (curbuf->b_u_synced
+			|| (bufref_valid(&save_curbuf)
+			    && curbuf == save_curbuf.br_buf
+			    && tick != CHANGEDTICK(curbuf)))
+		{
+		    // The command synced undo or changed this buffer.
+		    // Save the cursor line before the next typed edit.
 		    ins_need_undo = TRUE;
+		}
 	    }
 	    break;
 
@@ -2503,7 +2512,9 @@ stop_arrow(void)
     {
 	if (u_save_cursor() == OK)
 	{
-	    // A command or event may have moved the cursor after syncing undo.
+	    // A command or event may have moved the cursor or edited the
+	    // buffer. Update Insstart so that later edits can properly decide
+	    // whether an extra undo entry is needed.
 	    Insstart = curwin->w_cursor;
 	    Insstart_textlen = (colnr_T)linetabsize_str(ml_get_curline());
 	    ins_need_undo = FALSE;

src/evalfunc.c

@@ -1934,6 +1934,11 @@ typedef struct
 #else
 # define TERM_FUNC(name) NULL
 #endif
+#ifdef FEAT_TABPANEL
+# define TABPANEL_FUNC(name) name
+#else
+# define TABPANEL_FUNC(name) NULL
+#endif
 
 static const funcentry_T global_functions[] =
 {
@@ -2991,6 +2996,10 @@ static const funcentry_T global_functions[] =
 			ret_number,	    f_tabpagenr},
     {"tabpagewinnr",	1, 2, FEARG_1,	    arg2_number_string,
 			ret_number,	    f_tabpagewinnr},
+    {"tabpanel_getinfo", 0, 0, 0,	    NULL,
+			ret_dict_any,	    TABPANEL_FUNC(f_tabpanel_getinfo)},
+    {"tabpanel_scroll",	1, 2, FEARG_1,	    arg2_number_dict_any,
+			ret_bool,	    TABPANEL_FUNC(f_tabpanel_scroll)},
     {"tagfiles",	0, 0, 0,	    NULL,
 			ret_list_string,    f_tagfiles},
     {"taglist",		1, 2, FEARG_1,	    arg2_string,

src/optionstr.c

@@ -30,7 +30,7 @@ static char *(p_briopt_values[]) = {"shift:", "min:", "sbr", "list:", "column:",
 #endif
 #if defined(FEAT_TABPANEL)
 // Note: Keep this in sync with tabpanelopt_changed()
-static char *(p_tplo_values[]) = {"align:", "columns:", "vert", NULL};
+static char *(p_tplo_values[]) = {"align:", "columns:", "scrollbar", "vert", NULL};
 static char *(p_tplo_align_values[]) = {"left", "right", NULL};
 #endif
 #if defined(FEAT_DIFF)
@@ -4384,6 +4384,10 @@ expand_set_spellsuggest(optexpand_T *args, int *numMatches, char_u ***matches)
     char *
 did_set_splitkeep(optset_T *args UNUSED)
 {
+    win_T	*wp;
+    tabpage_T	*tp;
+    FOR_ALL_TAB_WINDOWS(tp, wp)
+	wp->w_prev_height = wp->w_height;
     return did_set_opt_strings(p_spk, p_spk_values, FALSE);
 }
 

src/proto/tabpanel.pro

@@ -1,5 +1,6 @@
 /* tabpanel.c */
 int tabpanelopt_changed(void);
+void tabpanel_forget_tabpage(const tabpage_T *tp);
 int tabpanel_width(void);
 int tabpanel_leftcol(void);
 void draw_tabpanel(void);
@@ -8,4 +9,7 @@ bool mouse_on_tabpanel(void);
 bool mouse_on_tabpanel_scrollbar(void);
 bool tabpanel_drag_scrollbar(int screen_row);
 bool tabpanel_scroll(int dir, int count);
+bool tabpanel_set_offset(int offset);
+void f_tabpanel_getinfo(typval_T *argvars, typval_T *rettv);
+void f_tabpanel_scroll(typval_T *argvars, typval_T *rettv);
 /* vim: set ft=c : */

src/tabpanel.c

@@ -43,11 +43,11 @@ static int opt_scope = OPT_LOCAL;
 static int tpl_align = ALIGN_LEFT;
 static int tpl_columns = 20;
 static bool tpl_is_vert = false;
-static bool tpl_scroll = false;
 static bool tpl_scrollbar = false;
 static int tpl_scroll_offset = 0;
 static int tpl_total_rows = 0;
-static int tpl_scrollbar_col = -1;	// screen column of scrollbar, -1 if none
+static int tpl_scrollbar_col = -1;  // screen column of scrollbar, -1 if none
+static tabpage_T *tpl_last_curtab = NULL;   // last curtab seen by draw_tabpanel
 
 typedef struct {
     win_T   *wp;
@@ -69,7 +69,6 @@ tabpanelopt_changed(void)
     int		new_align = ALIGN_LEFT;
     long	new_columns = 20;
     bool	new_is_vert = false;
-    bool	new_scroll = false;
     bool	new_scrollbar = false;
 
     p = p_tplo;
@@ -107,12 +106,6 @@ tabpanelopt_changed(void)
 	{
 	    p += 9;
 	    new_scrollbar = true;
-	    new_scroll = true;
-	}
-	else if (STRNCMP(p, "scroll", 6) == 0)
-	{
-	    p += 6;
-	    new_scroll = true;
 	}
 
 	if (*p != ',' && *p != NUL)
@@ -124,15 +117,26 @@ tabpanelopt_changed(void)
     tpl_align = new_align;
     tpl_columns = new_columns;
     tpl_is_vert = new_is_vert;
-    if (tpl_scroll != new_scroll)
-	tpl_scroll_offset = 0;
-    tpl_scroll = new_scroll;
     tpl_scrollbar = new_scrollbar;
 
+    // Re-center the current tab on the next redraw.
+    tpl_last_curtab = NULL;
+
     shell_new_columns();
     return OK;
 }
 
+/*
+ * Drop any internal reference to "tp", so draw_tabpanel() never compares
+ * against a dangling pointer after the tabpage has been freed.
+ */
+    void
+tabpanel_forget_tabpage(const tabpage_T *tp)
+{
+    if (tpl_last_curtab == tp)
+	tpl_last_curtab = NULL;
+}
+
 /*
  * Return the width of tabpanel.
  */
@@ -264,6 +268,31 @@ tabpanel_append_click_regions(
     }
 }
 
+/*
+ * Ensure the current tab is visible by adjusting tpl_scroll_offset when
+ * the selected tab has changed since the previous redraw.  Mouse wheel or
+ * scrollbar drag operations leave curtab unchanged, so the user's chosen
+ * offset is preserved in those cases.
+ */
+    static void
+follow_curtab_if_needed(int curtab_row)
+{
+    if (Rows <= 0 || curtab == tpl_last_curtab)
+	return;
+
+    if (curtab_row < tpl_scroll_offset)
+	tpl_scroll_offset = curtab_row;
+    else if (curtab_row >= tpl_scroll_offset + Rows)
+	tpl_scroll_offset = curtab_row - Rows + 1;
+
+    int max_offset = tpl_total_rows > Rows ? tpl_total_rows - Rows : 0;
+
+    if (tpl_scroll_offset < 0)
+	tpl_scroll_offset = 0;
+    else if (tpl_scroll_offset > max_offset)
+	tpl_scroll_offset = max_offset;
+}
+
 /*
  * draw the tabpanel.
  */
@@ -293,30 +322,36 @@ draw_tabpanel(void)
     int sb_len = tpl_scrollbar ? SCROLL_LEN : 0;
     int sb_screen_col = -1;
 
+    // The scrollbar is always placed at the right edge of the tabpanel,
+    // regardless of 'align'.  The vertical separator sits at the panel's
+    // boundary with the buffer area (left edge for align:right, right edge
+    // for align:left).
     if (tpl_is_vert)
     {
 	if (is_right)
 	{
-	    // draw main contents in tabpanel
-	    do_by_tplmode(TPLMODE_GET_CURTAB_ROW, VERT_LEN + sb_len,
-		    maxwidth - VERT_LEN, &curtab_row, NULL);
-	    do_by_tplmode(TPLMODE_REDRAW, VERT_LEN + sb_len, maxwidth,
+	    // Panel on the right: vert at panel's left edge, scrollbar at
+	    // panel's right edge (= screen's right edge).
+	    do_by_tplmode(TPLMODE_GET_CURTAB_ROW, VERT_LEN,
+		    maxwidth - sb_len, &curtab_row, NULL);
+	    follow_curtab_if_needed(curtab_row);
+	    do_by_tplmode(TPLMODE_REDRAW, VERT_LEN, maxwidth - sb_len,
 		    &curtab_row, NULL);
-	    // draw vert separator in tabpanel
 	    for (vsrow = 0; vsrow < Rows; vsrow++)
 		screen_putchar(curwin->w_fill_chars.tpl_vert, vsrow,
 			topframe->fr_width, vs_attr);
 	    if (tpl_scrollbar)
-		sb_screen_col = topframe->fr_width + VERT_LEN;
+		sb_screen_col = topframe->fr_width + maxwidth - SCROLL_LEN;
 	}
 	else
 	{
-	    // draw main contents in tabpanel
+	    // Panel on the left: scrollbar just left of vert, vert at
+	    // panel's right edge (boundary with buffer).
 	    do_by_tplmode(TPLMODE_GET_CURTAB_ROW, 0,
 		    maxwidth - VERT_LEN - sb_len, &curtab_row, NULL);
+	    follow_curtab_if_needed(curtab_row);
 	    do_by_tplmode(TPLMODE_REDRAW, 0, maxwidth - VERT_LEN - sb_len,
 		    &curtab_row, NULL);
-	    // draw vert separator in tabpanel
 	    for (vsrow = 0; vsrow < Rows; vsrow++)
 		screen_putchar(curwin->w_fill_chars.tpl_vert, vsrow,
 			maxwidth - VERT_LEN, vs_attr);
@@ -328,16 +363,20 @@ draw_tabpanel(void)
     {
 	if (is_right)
 	{
-	    do_by_tplmode(TPLMODE_GET_CURTAB_ROW, sb_len, maxwidth,
+	    // Panel on the right, no vert: scrollbar at screen's right edge.
+	    do_by_tplmode(TPLMODE_GET_CURTAB_ROW, 0, maxwidth - sb_len,
+		    &curtab_row, NULL);
+	    follow_curtab_if_needed(curtab_row);
+	    do_by_tplmode(TPLMODE_REDRAW, 0, maxwidth - sb_len,
 		    &curtab_row, NULL);
-	    do_by_tplmode(TPLMODE_REDRAW, sb_len, maxwidth, &curtab_row, NULL);
 	    if (tpl_scrollbar)
-		sb_screen_col = topframe->fr_width;
+		sb_screen_col = topframe->fr_width + maxwidth - SCROLL_LEN;
 	}
 	else
 	{
 	    do_by_tplmode(TPLMODE_GET_CURTAB_ROW, 0, maxwidth - sb_len,
 		    &curtab_row, NULL);
+	    follow_curtab_if_needed(curtab_row);
 	    do_by_tplmode(TPLMODE_REDRAW, 0, maxwidth - sb_len,
 		    &curtab_row, NULL);
 	    if (tpl_scrollbar)
@@ -354,6 +393,7 @@ draw_tabpanel(void)
     // A user function may reset KeyTyped, restore it.
     KeyTyped = saved_KeyTyped;
 
+    tpl_last_curtab = curtab;
     redraw_tabpanel = FALSE;
 }
 
@@ -606,13 +646,7 @@ do_by_tplmode(
     args.col_end = col_end;
 
     if (tplmode != TPLMODE_GET_CURTAB_ROW && args.maxrow > 0)
-    {
-	if (tpl_scroll)
-	    args.offsetrow = tpl_scroll_offset;
-	else
-	    while (args.offsetrow + args.maxrow <= *pcurtab_row)
-		args.offsetrow += args.maxrow;
-    }
+	args.offsetrow = tpl_scroll_offset;
 
     tp = first_tabpage;
 
@@ -632,16 +666,9 @@ do_by_tplmode(
 	{
 	    args.attr = attr_tpls;
 	    if (tplmode == TPLMODE_GET_CURTAB_ROW)
-	    {
+		// Capture the row of the current tab and keep iterating so
+		// tpl_total_rows receives the true content height below.
 		*pcurtab_row = row;
-		// When scroll mode is active keep iterating so tpl_total_rows
-		// receives the true content height; otherwise bail out early.
-		if (!tpl_scroll)
-		{
-		    do_unlet((char_u *)"g:actual_curtabpage", TRUE);
-		    break;
-		}
-	    }
 	}
 	else
 	    args.attr = attr_tpl;
@@ -742,7 +769,7 @@ do_by_tplmode(
     // Capture the true content height during the GET_CURTAB_ROW pass, which
     // ignores maxrow and therefore walks every tab.  REDRAW stops at the
     // visible edge so its "row" is clamped and unusable here.
-    if (tplmode == TPLMODE_GET_CURTAB_ROW && tpl_scroll)
+    if (tplmode == TPLMODE_GET_CURTAB_ROW)
 	tpl_total_rows = row;
 }
 
@@ -761,10 +788,21 @@ draw_tabpanel_scrollbar(int screen_col)
 
     if (tpl_total_rows > Rows && Rows > 0)
     {
+	int max_offset = tpl_total_rows - Rows;
+	int track_range;
+
 	thumb_height = Rows * Rows / tpl_total_rows;
 	if (thumb_height < 1)
 	    thumb_height = 1;
-	thumb_top = Rows * tpl_scroll_offset / tpl_total_rows;
+
+	// Map tpl_scroll_offset onto the track: at offset 0 the thumb's top
+	// is at row 0, at the maximum offset its bottom reaches the last
+	// row.  This is the exact inverse of tabpanel_drag_scrollbar().
+	track_range = Rows - thumb_height;
+	if (track_range > 0 && max_offset > 0)
+	    thumb_top = track_range * tpl_scroll_offset / max_offset;
+	else
+	    thumb_top = 0;
 	if (thumb_top + thumb_height > Rows)
 	    thumb_top = Rows - thumb_height;
 	if (thumb_top < 0)
@@ -848,7 +886,6 @@ tabpanel_drag_scrollbar(int screen_row)
 /*
  * Scroll the tabpanel by 'count' rows in direction 'dir' (1 = down, -1 = up).
  * Returns true if the offset changed and a redraw was scheduled.
- * Has no effect unless 'tabpanelopt' contains "scroll".
  */
     bool
 tabpanel_scroll(int dir, int count)
@@ -856,7 +893,7 @@ tabpanel_scroll(int dir, int count)
     int max_offset;
     int new_offset;
 
-    if (!tpl_scroll || tabpanel_width() == 0)
+    if (tabpanel_width() == 0)
 	return false;
 
     max_offset = tpl_total_rows - Rows;
@@ -876,4 +913,102 @@ tabpanel_scroll(int dir, int count)
     return true;
 }
 
+/*
+ * Set the tabpanel scroll offset to "offset" (clamped to the valid range).
+ * Returns true if the offset changed and a redraw was scheduled.
+ */
+    bool
+tabpanel_set_offset(int offset)
+{
+    int max_offset;
+
+    if (tabpanel_width() == 0)
+	return false;
+
+    max_offset = tpl_total_rows - Rows;
+    if (max_offset < 0)
+	max_offset = 0;
+
+    if (offset < 0)
+	offset = 0;
+    if (offset > max_offset)
+	offset = max_offset;
+    if (offset == tpl_scroll_offset)
+	return false;
+
+    tpl_scroll_offset = offset;
+    redraw_tabpanel = TRUE;
+    return true;
+}
+
+/*
+ * "tabpanel_getinfo()" function
+ */
+    void
+f_tabpanel_getinfo(typval_T *argvars UNUSED, typval_T *rettv)
+{
+    dict_T	*d;
+    int		max_offset;
+
+    if (rettv_dict_alloc(rettv) == FAIL)
+	return;
+    d = rettv->vval.v_dict;
+
+    max_offset = tpl_total_rows - Rows;
+    if (max_offset < 0)
+	max_offset = 0;
+
+    dict_add_string(d, "align",
+	    (char_u *)(tpl_align == ALIGN_RIGHT ? "right" : "left"));
+    dict_add_number(d, "columns", tabpanel_width());
+    dict_add_bool(d, "scrollbar", tpl_scrollbar);
+    dict_add_number(d, "offset", tpl_scroll_offset);
+    dict_add_number(d, "total", tpl_total_rows);
+    dict_add_number(d, "max_offset", max_offset);
+}
+
+/*
+ * "tabpanel_scroll()" function
+ */
+    void
+f_tabpanel_scroll(typval_T *argvars, typval_T *rettv)
+{
+    varnumber_T	n;
+    int		absolute = 0;
+    bool	changed;
+
+    rettv->v_type = VAR_BOOL;
+    rettv->vval.v_number = VVAL_FALSE;
+
+    if (in_vim9script()
+	    && (check_for_number_arg(argvars, 0) == FAIL
+		|| check_for_opt_dict_arg(argvars, 1) == FAIL))
+	return;
+
+    n = tv_get_number_chk(&argvars[0], NULL);
+    if (argvars[1].v_type != VAR_UNKNOWN)
+    {
+	if (argvars[1].v_type != VAR_DICT || argvars[1].vval.v_dict == NULL)
+	{
+	    emsg(_(e_dictionary_required));
+	    return;
+	}
+	absolute = dict_get_bool(argvars[1].vval.v_dict, "absolute", FALSE);
+    }
+
+    // Clamp to int range to avoid signed overflow when casting and negating.
+    if (n > INT_MAX)
+	n = INT_MAX;
+    else if (n < -INT_MAX)
+	n = -INT_MAX;
+
+    if (absolute)
+	changed = tabpanel_set_offset((int)n);
+    else
+	changed = tabpanel_scroll(n >= 0 ? 1 : -1,
+				  (int)(n >= 0 ? n : -n));
+
+    rettv->vval.v_number = changed ? VVAL_TRUE : VVAL_FALSE;
+}
+
 #endif // FEAT_TABPANEL

src/testdir/Makefile

@@ -2,6 +2,11 @@
 # Makefile to run all tests for Vim
 #
 
+# The old-style tests (*.in) use shared filenames in the working directory
+# (test.ok, test.out, X*, viminfo), so running them in parallel causes races
+# and spurious failures.
+.NOTPARALLEL:
+
 # Use console or GUI.
 VIMPROG = ../vim
 XXDPROG = ../xxd/xxd

src/testdir/dumps/Test_tabpanel_many_tabpages_4.dump

@@ -1,10 +1,10 @@
-|1+2&#ffffff0@1|:|t|a|b| @3> +0&&@34
+|5+8#0000001#e0e0e08|:|t|a|b| @4> +0#0000000#ffffff0@34
+|6+8#0000001#e0e0e08|:|t|a|b| @4|~+0#4040ff13#ffffff0| @33
+|7+8#0000001#e0e0e08|:|t|a|b| @4|~+0#4040ff13#ffffff0| @33
+|8+8#0000001#e0e0e08|:|t|a|b| @4|~+0#4040ff13#ffffff0| @33
+|9+8#0000001#e0e0e08|:|t|a|b| @4|~+0#4040ff13#ffffff0| @33
+|1+8#0000001#e0e0e08|0|:|t|a|b| @3|~+0#4040ff13#ffffff0| @33
+|1+2#0000000&@1|:|t|a|b| @3|~+0#4040ff13&| @33
 |1+8#0000001#e0e0e08|2|:|t|a|b| @3|~+0#4040ff13#ffffff0| @33
 |1+8#0000001#e0e0e08|3|:|t|a|b| @3|~+0#4040ff13#ffffff0| @33
-|1+8#0000001#e0e0e08|4|:|t|a|b| @3|~+0#4040ff13#ffffff0| @33
-|1+8#0000001#e0e0e08|5|:|t|a|b| @3|~+0#4040ff13#ffffff0| @33
-|1+8#0000001#e0e0e08|6|:|t|a|b| @3|~+0#4040ff13#ffffff0| @33
-|1+8#0000001#e0e0e08|7|:|t|a|b| @3|~+0#4040ff13#ffffff0| @33
-|1+8#0000001#e0e0e08|8|:|t|a|b| @3|~+0#4040ff13#ffffff0| @33
-|1+8#0000001#e0e0e08|9|:|t|a|b| @3|~+0#4040ff13#ffffff0| @33
-|2+8#0000001#e0e0e08|0|:|t|a|b| @3|:+0#0000000#ffffff0|t|a|b|n|e|x|t| |-|3| @6|0|,|0|-|1| @7|A|l@1| 
+|1+8#0000001#e0e0e08|4|:|t|a|b| @3|:+0#0000000#ffffff0|t|a|b|n|e|x|t| |-|3| @6|0|,|0|-|1| @7|A|l@1| 

src/testdir/test_channel.vim

@@ -2933,13 +2933,15 @@ func Test_error_callback_terminal()
   unlet! g:out g:error
 endfunc
 
-" Verify that term_start() with out_cb/err_cb delivers one line per callback
-" call (no embedded newlines, no trailing CR), matching the user's expectation.
-func Test_term_start_cb_per_line()
+" Verify that term_start() with out_cb/err_cb delivers data in RAW mode,
+" preserving embedded newlines in the raw chunk received from read().  If
+" per-line handling is desired, it is the callback's responsibility to split
+" on NL and strip the trailing CR.
+func Test_term_start_cb_raw_chunk()
   CheckUnix
   CheckFeature terminal
   let g:Ch_msgs = []
-  let script_file = 'Xterm_cb_per_line.sh'
+  let script_file = 'Xterm_cb_raw_chunk.sh'
   call writefile(["#!/bin/sh",
         \         "printf 'err:1\\nerr:2\\n' >&2",
         \         "printf 'out:3\\n'"], script_file, 'D')
@@ -2947,10 +2949,16 @@ func Test_term_start_cb_per_line()
   let ptybuf = term_start('./' .. script_file, {
         \ 'out_cb': {ch, msg -> add(g:Ch_msgs, msg)},
         \ 'err_cb': {ch, msg -> add(g:Ch_msgs, msg)}})
-  call WaitForAssert({-> assert_equal(3, len(g:Ch_msgs))}, 5000)
-  " Each line must arrive as a separate callback call with no embedded CR/NL.
-  call assert_equal(['err:1', 'err:2', 'out:3'], g:Ch_msgs)
+  " Wait until both the raw stderr chunk and a stdout chunk have arrived.
+  call WaitForAssert({-> assert_true(
+        \ index(g:Ch_msgs, "err:1\nerr:2\n") >= 0
+        \ && match(g:Ch_msgs, 'out:3') >= 0)}, 5000)
+  " stderr (via pipe) arrives as a single raw chunk with embedded NL,
+  " not split per line.  stdout (via PTY) is delivered, but its exact
+  " CR/LF shape depends on the PTY line discipline, so we only check that
+  " 'out:3' appears somewhere in the received chunks.
   call job_stop(term_getjob(ptybuf))
+  exe 'bwipe! ' .. ptybuf
   unlet g:Ch_msgs
 endfunc
 

src/testdir/test_options.vim

@@ -593,6 +593,12 @@ func Test_set_completion_string_values()
   if exists('+tabclose')
     call assert_equal('left uselast', join(sort(getcompletion('set tabclose=', 'cmdline'))), ' ')
   endif
+  if has('tabpanel')
+    call assert_equal(['align:', 'columns:', 'scrollbar', 'vert'],
+          \ getcompletion('set tabpanelopt=', 'cmdline'))
+    call assert_equal(['left', 'right'],
+          \ getcompletion('set tabpanelopt=align:', 'cmdline'))
+  endif
   if exists('+termwintype')
     call assert_equal('conpty', getcompletion('set termwintype=', 'cmdline')[1])
   endif

src/testdir/test_tabpanel.vim

@@ -963,49 +963,26 @@ func Test_tabpanel_large_columns()
   call assert_fails(':set tabpanelopt=columns:-1', 'E474:')
 endfunc
 
-func Test_tabpanel_scrollopt_accepted()
-  " 'scroll' / 'scrollbar' must be accepted in 'tabpanelopt'.
-  set tabpanelopt=scroll
-  call assert_equal('scroll', &tabpanelopt)
-  set tabpanelopt=scrollbar
-  call assert_equal('scrollbar', &tabpanelopt)
-
-  " Combination with other values.
-  set tabpanelopt=align:right,scroll
-  call assert_equal('align:right,scroll', &tabpanelopt)
-  set tabpanelopt=columns:15,vert,scrollbar
-  call assert_equal('columns:15,vert,scrollbar', &tabpanelopt)
-  set tabpanelopt=align:right,columns:12,vert,scrollbar
-  call assert_equal('align:right,columns:12,vert,scrollbar', &tabpanelopt)
-
-  " Unknown values must still fail.
-  call assert_fails(':set tabpanelopt=scrol', 'E474:')
-  call assert_fails(':set tabpanelopt=scrollbarx', 'E474:')
-
-  call s:reset()
-endfunc
-
 func Test_tabpanel_scroll_many_tabs()
   let save_lines = &lines
   let save_showtabpanel = &showtabpanel
   let save_tabpanelopt = &tabpanelopt
 
-  " Make the screen short so the tab list exceeds the visible height.
+  " Make the screen short so the tab page list exceeds the visible height.
   set lines=8
   set showtabpanel=2
-  set tabpanelopt=scroll
+  set tabpanelopt=
   for i in range(20)
     tabnew
   endfor
 
-  " Should not crash with many tabs and scroll enabled.
+  " Should not crash with many tabs (scroll behaviour is always on).
   redraw!
 
-  " Switching to scrollbar resets the offset but must also not crash.
+  " Toggling scrollbar must also not crash.
   set tabpanelopt=scrollbar
   redraw!
 
-  " Disabling scroll returns to normal behavior.
   set tabpanelopt=
   redraw!
 
@@ -1024,6 +1001,94 @@ func Test_tabpanel_scroll_many_tabs()
   let &lines = save_lines
 endfunc
 
+" The scrollbar thumb must follow the current tab when it is moved by
+" gt/gT/:tabnext/:tablast, so that the selected tab is always visible.
+func Test_tabpanel_scrollbar_follows_curtab()
+  let save_lines = &lines
+  let save_columns = &columns
+  let save_showtabpanel = &showtabpanel
+  let save_tabpanelopt = &tabpanelopt
+
+  set lines=10 columns=40
+  set showtabpanel=2 tabpanelopt=scrollbar,columns:8
+  for i in range(49)
+    tabnew
+  endfor
+  let sb_col = 8
+
+  " With curtab at the top of the list, row 1 shows the thumb and the
+  " last row shows the track.  Record the two attrs for comparison.
+  tabfirst
+  redraw
+  let attr_thumb = screenattr(1, sb_col)
+  let attr_track = screenattr(&lines, sb_col)
+  call assert_notequal(attr_thumb, attr_track)
+
+  " Jump to a tab far outside the visible range: thumb must leave the top.
+  30tabnext
+  redraw
+  call assert_equal(attr_track, screenattr(1, sb_col))
+
+  " Back to the first tab: thumb returns to the top.
+  tabfirst
+  redraw
+  call assert_equal(attr_thumb, screenattr(1, sb_col))
+  call assert_equal(attr_track, screenattr(&lines, sb_col))
+
+  " gT from the first tab wraps to the last: thumb moves to the bottom.
+  normal! gT
+  redraw
+  call assert_equal(attr_track, screenattr(1, sb_col))
+  call assert_equal(attr_thumb, screenattr(&lines, sb_col))
+
+  " gt from the last tab wraps to the first: thumb returns to the top.
+  normal! gt
+  redraw
+  call assert_equal(attr_thumb, screenattr(1, sb_col))
+  call assert_equal(attr_track, screenattr(&lines, sb_col))
+
+  %bwipeout!
+  let &tabpanelopt = save_tabpanelopt
+  let &showtabpanel = save_showtabpanel
+  let &lines = save_lines
+  let &columns = save_columns
+endfunc
+
+" With 31 tabs on 24 rows, :tablast must place the scrollbar thumb's
+" bottom at the last screen row.  Before the fix, integer truncation in
+" thumb_top left a one-row gap at the bottom.
+func Test_tabpanel_scrollbar_reaches_bottom()
+  let save_lines = &lines
+  let save_columns = &columns
+  let save_showtabpanel = &showtabpanel
+  let save_tabpanelopt = &tabpanelopt
+
+  set lines=24 columns=40
+  set showtabpanel=2 tabpanelopt=scrollbar,columns:8
+  for i in range(30)
+    tabnew
+  endfor
+  let sb_col = 8
+
+  " Identify the thumb attr while the thumb is at the top.
+  tabfirst
+  redraw
+  let attr_thumb = screenattr(1, sb_col)
+  let attr_track = screenattr(&lines, sb_col)
+  call assert_notequal(attr_thumb, attr_track)
+
+  " :tablast must push the thumb all the way to the bottom.
+  tablast
+  redraw
+  call assert_equal(attr_thumb, screenattr(&lines, sb_col))
+
+  %bwipeout!
+  let &tabpanelopt = save_tabpanelopt
+  let &showtabpanel = save_showtabpanel
+  let &lines = save_lines
+  let &columns = save_columns
+endfunc
+
 func Test_tabpanel_variable_height()
 
   let save_lines = &lines
@@ -1064,4 +1129,81 @@ func Test_tabpanel_empty()
   set tabpanel&
 endfunc
 
+func Test_tabpanel_getinfo_and_scroll()
+  CheckScreendump
+
+  let lines =<< trim END
+    set showtabpanel=2 tabpanelopt=columns:20
+    set showtabline=0
+    for i in range(40)
+      tabnew
+    endfor
+    tabfirst
+    redraw
+    func WriteResult(label)
+      call writefile([a:label, string(tabpanel_getinfo())], 'Xresult', 'a')
+    endfunc
+    call delete('Xresult')
+    call WriteResult('initial')
+    let g:r1 = tabpanel_scroll(1)
+    redraw
+    call WriteResult('after_scroll_1')
+    call tabpanel_scroll(-10)
+    redraw
+    call WriteResult('after_scroll_minus10')
+    let g:max = tabpanel_getinfo().max_offset
+    call tabpanel_scroll(g:max, #{absolute: 1})
+    redraw
+    call WriteResult('after_abs_max')
+    call tabpanel_scroll(99999, #{absolute: 1})
+    redraw
+    call WriteResult('after_abs_overflow')
+    call tabpanel_scroll(-5, #{absolute: 1})
+    redraw
+    call WriteResult('after_abs_negative')
+    let g:r_zero = tabpanel_scroll(0, #{absolute: 1})
+    let g:r_neg_at_zero = tabpanel_scroll(-1)
+    call writefile([
+          \ 'r1=' .. g:r1,
+          \ 'max=' .. g:max,
+          \ 'r_zero=' .. g:r_zero,
+          \ 'r_neg_at_zero=' .. g:r_neg_at_zero,
+          \ ], 'Xflags')
+  END
+  call writefile(lines, 'XTest_tabpanel_getinfo', 'D')
+
+  let buf = RunVimInTerminal('-S XTest_tabpanel_getinfo', {'rows': 10, 'cols': 45})
+  call WaitForAssert({-> assert_true(filereadable('Xflags'))})
+  call StopVimInTerminal(buf)
+
+  let results = readfile('Xresult')
+  let flags = readfile('Xflags')
+  call delete('Xresult')
+  call delete('Xflags')
+
+  " Parse [label, dict] pairs.
+  let info = {}
+  for i in range(0, len(results) - 1, 2)
+    let info[results[i]] = eval(results[i + 1])
+  endfor
+
+  call assert_equal('left', info.initial.align)
+  call assert_equal(20, info.initial.columns)
+  call assert_false(has_key(info.initial, 'scroll'))
+  call assert_equal(0, info.initial.offset)
+  call assert_true(info.initial.total > 0)
+  call assert_true(info.initial.max_offset > 0)
+
+  call assert_equal(1, info.after_scroll_1.offset)
+  call assert_equal(0, info.after_scroll_minus10.offset)
+
+  let max = info.initial.max_offset
+  call assert_equal(max, info.after_abs_max.offset)
+  call assert_equal(max, info.after_abs_overflow.offset)
+  call assert_equal(0, info.after_abs_negative.offset)
+
+  call assert_equal(['r1=v:true', 'max=' .. max,
+        \ 'r_zero=v:false', 'r_neg_at_zero=v:false'], flags)
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab

src/testdir/test_undo.vim

@@ -939,4 +939,32 @@ func Test_undo_line_backspace_after_insert_cmd_cursor_movement()
   bwipe!
 endfunc
 
+func Test_undo_line_backspace_after_insert_func_edit()
+  new
+  setlocal backspace=eol undolevels=100
+
+  let v:errmsg = ''
+  call feedkeys("i\<CR>"
+        \ .. "\<Cmd>call setline(2, 'abc')\<CR>"
+        \ .. "\<BS>\<Esc>u", 'xt')
+
+  call assert_equal('', v:errmsg)
+  call assert_equal([''], getline(1, '$'))
+  bwipe!
+endfunc
+
+func Test_undo_line_backspace_after_insert_cmd_edit()
+  new
+  setlocal backspace=eol undolevels=100
+
+  let v:errmsg = ''
+  call feedkeys("i\<CR>"
+        \ .. "\<Cmd>s/.*/abc/\<CR>"
+        \ .. "\<BS>\<Esc>u", 'xt')
+
+  call assert_equal('', v:errmsg)
+  call assert_equal([''], getline(1, '$'))
+  bwipe!
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab

src/testdir/test_window_cmd.vim

@@ -1992,6 +1992,16 @@ func Test_splitkeep_screen_cursor_pos()
   set splitkeep&
 endfunc
 
+func Test_splitkeep_cmdheight()
+  set splitkeep=screen
+  call setline(1, range(&lines))
+  norm! G
+  set cmdheight=2
+  call assert_equal(&lines - 1, line('.'))
+  %bwipeout!
+  set splitkeep& cmdheight&
+endfunc
+
 func Test_splitkeep_cursor()
   CheckScreendump
   let lines =<< trim END

src/testdir/util/gen_opt_test.vim

@@ -330,9 +330,11 @@ let test_values = {
       \ 'tabline': [['', 'xxx'], ['%$', '%{', '%{%', '%{%}', '%(', '%)']],
       \ 'tabpanel': [['', 'aaa', 'bbb'], []],
       \ 'tabpanelopt': [['', 'align:left', 'align:right', 'vert', 'columns:0',
-      \		'columns:20', 'columns:999'],
+      \		'columns:20', 'columns:999', 'scrollbar',
+      \		'columns:15,vert,scrollbar',
+      \		'align:right,columns:12,vert,scrollbar'],
       \		['xxx', 'align:', 'align:middle', 'colomns:', 'cols:10',
-      \		'cols:-1']],
+      \		'cols:-1', 'scroll', 'scrol', 'scrollbarx']],
       \ 'tagcase': [['followic', 'followscs', 'ignore', 'match', 'smart'],
       \		['', 'xxx', 'smart,match']],
       \ 'termencoding': [has('gui_gtk') ? [] : ['', 'utf-8'], ['xxx']],

src/version.c

@@ -729,6 +729,22 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    413,
+/**/
+    412,
+/**/
+    411,
+/**/
+    410,
+/**/
+    409,
+/**/
+    408,
+/**/
+    407,
+/**/
+    406,
 /**/
     405,
 /**/

src/window.c

@@ -4784,6 +4784,9 @@ free_tabpage(tabpage_T *tp)
 
     if (tp == lastused_tabpage)
 	lastused_tabpage = NULL;
+#ifdef FEAT_TABPANEL
+    tabpanel_forget_tabpage(tp);
+#endif
 
     vim_free(tp->tp_localdir);
     vim_free(tp->tp_prevdir);
@@ -7588,6 +7591,7 @@ command_height(void)
     }
     if (p_ch < old_p_ch && command_frame_height && frp != NULL)
 	frame_add_height(frp, (int)(old_p_ch - p_ch));
+    win_fix_scroll(true);
 
     // Recompute window positions.
     win_comp_pos();