doc: Misc. X11-related cleanups

These were all introduced by the previous commit, and spotted with with
`make html` in `runtime/doc`.

[ci skip]

runtime/doc/eval.txt

@@ -1562,9 +1562,7 @@ v:progname	Contains the name (with path removed) with which Nvim was
 
 					*v:progpath* *progpath-variable*
 v:progpath	Contains the command with which Vim was invoked, including the
-		path.  Useful if you want to message a Vim server using a
+		path. To get the full path use: >
-		|--remote-expr|.
-		To get the full path use: >
 			echo exepath(v:progpath)
 <		NOTE: This does not work when the command is a relative path
 		and the current directory has changed.
@@ -1694,13 +1692,8 @@ v:version	Version number of Vim: Major version number times 100 plus
 					*v:warningmsg* *warningmsg-variable*
 v:warningmsg	Last given warning message.  It's allowed to set this variable.
 
-					*v:windowid* *windowid-variable*
+					*v:windowid* *windowid-variable* {Nvim}
-v:windowid	When any X11 based GUI is running or when running in a
+v:windowid	Is a no-op at the moment; the value is always set to 0.
-		terminal and Vim connects to the X server (|-X|) this will be
-		set to the window ID.
-		When an MS-Windows GUI is running this will be set to the
-		window handle.
-		Otherwise the value is zero.
 		Note: for windows inside Vim use |winnr()|.
 
 ==============================================================================
@@ -5388,8 +5381,9 @@ serverlist()						*serverlist()*
 		When there are no servers an empty string is returned.
 		Example: >
 			:echo serverlist()
-<							*--serverlist*
+<						{Nvim} *--serverlist*
-		The Vim command-line option `--serverlist` can be imitated: >
+		The Vim command-line option `--serverlist` was removed from
+		Nvim, but it can be imitated if needed: >
 			nvim --cmd "echo serverlist()" --cmd "q"
 <
 serverstart([{address}])				*serverstart()*

runtime/doc/gui_w32.txt

@@ -51,16 +51,6 @@ vimrc or gvimrc file: >
 There is a specific version of gvim.exe that runs under the Win32s subsystem
 of Windows 3.1 or 3.11.  See |win32s|.
 
-
-Using Vim as a plugin					*gui-w32-windowid*
-
-When gvim starts up normally, it creates its own top level window.  If you
-pass Vim the command-line option |--windowid| with a decimal or hexadecimal
-value, Vim will create a window that is a child of the window with the given
-ID.  This enables Vim to act as a plugin in another application.  This really
-is a programmer's interface, and is of no use without a supporting application
-to spawn Vim correctly.
-
 ==============================================================================
 2. Vim as default editor				*vim-default-editor*
 

runtime/doc/gui_x11.txt

@@ -231,33 +231,6 @@ For example: >
   :10amenu File.Print :w !lpr -Php3
   :10vmenu File.Print :w !lpr -Php3
 <
-							*X11-icon*
-Vim uses a black&white icon by default when compiled with Motif or Athena.  A
-colored Vim icon is included as $VIMRUNTIME/vim32x32.xpm.  For GTK+, this is
-the builtin icon used.  Unfortunately, how you should install it depends on
-your window manager.  When you use this, remove the 'i' flag from
-'guioptions', to remove the black&white icon: >
-  :set guioptions-=i
-
-If you use one of the fvwm* family of window managers simply add this line to
-your .fvwm2rc configuration file: >
-
-  Style "vim"		Icon vim32x32.xpm
-
-Make sure the icon file's location is consistent with the window manager's
-ImagePath statement.  Either modify the ImagePath from within your .fvwm2rc or
-drop the icon into one the pre-defined directories: >
-
-  ImagePath /usr/X11R6/include/X11/pixmaps:/usr/X11R6/include/X11/bitmaps
-
-Note: older versions of fvwm use "IconPath" instead of "ImagePath".
-
-For CDE "dtwm" (a derivative of Motif) add this line in the .Xdefaults: >
-   Dtwm*Vim*iconImage: /usr/local/share/vim/vim32x32.xpm
-
-For "mwm" (Motif window manager) the line would be: >
-   Mwm*Vim*iconImage: /usr/local/share/vim/vim32x32.xpm
-
 Mouse Pointers Available in X11				*X11_mouse_shapes*
 
 By using the |'mouseshape'| option, the mouse pointer can be automatically
@@ -407,11 +380,6 @@ means in detail:
 - The internal variable |v:this_session| is not changed when storing the
   session.  Also, it is restored to its old value when logging in again.
 
-The position and size of the GUI window is not saved by Vim since doing so
-is the window manager's job.  But if compiled with GTK+ 2 support, Vim helps
-the WM to identify the window by restoring the window role (using the |--role|
-command line argument).
-
 ==============================================================================
 7. KDE version					*gui-kde* *kde* *KDE* *KVim*
 							*gui-x11-kde*

runtime/doc/message.txt

@@ -671,15 +671,6 @@ This mostly happens when the disk is full.  Vim could not write text into the
 text may be lost without recovery being possible.  Vim might run out of memory
 when this problem persists.
 
-						*connection-refused*  >
-  Xlib: connection to "<machine-name:0.0" refused by server
-
-This happens when Vim tries to connect to the X server, but the X server does
-not allow a connection.  The connection to the X server is needed to be able
-to restore the title and for the xterm clipboard support.  Unfortunately this
-error message cannot be avoided, except by disabling the |+xterm_clipboard|
-and |+X11| features.
-
 							*E10*  >
   \\ should be followed by /, ? or &
 

runtime/doc/options.txt

@@ -1381,11 +1381,8 @@ A jump table for the options with a short description can be found at |Q_op|.
 	"if,If,IF".
 
 						*'clipboard'* *'cb'*
-'clipboard' 'cb'	string	(default "autoselect,exclude:cons\|linux"
+'clipboard' 'cb'	string	(default "")
-						  for X-windows, "" otherwise)
 			global
-			{only in GUI versions or when the |+xterm_clipboard|
-			feature is included}
 	This option is a list of comma separated names.
 	These names are recognized:
 
@@ -1407,10 +1404,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 			register.  When "unnamed" is also included to the
 			option, yank operations (but not delete, change or
 			put) will additionally copy the text into register
-			'*'.
+			'*'. See |nvim-clipboard|.
-			Only available with the |+X11| feature.
-			Availability can be checked with: >
-				if has('unnamedplus')
 <
 						*clipboard-autoselect*
 	autoselect	Works like the 'a' flag in 'guioptions': If present,
@@ -1457,10 +1451,6 @@ A jump table for the options with a short description can be found at |Q_op|.
 			  console, but do want this in a terminal emulator.
 			To never connect to the X server use: >
 				exclude:.*
-<			This has the same effect as using the |-X| argument.
-			Note that when there is no connection to the X server
-			the window title won't be restored and the clipboard
-			cannot be accessed.
 			The value of 'magic' is ignored, {pattern} is
 			interpreted as if 'magic' was on.
 			The rest of the option value will be used for
@@ -3308,8 +3298,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 		GTK, Motif, Mac OS/X and MS-Windows.
 								*'go-i'*
 	  'i'	Use a Vim icon.  For GTK with KDE it is used in the left-upper
-		corner of the window.  It's black&white on non-GTK, because of
+		corner of the window.
-		limitations of X11.  For a color icon, see |X11-icon|.
 								*'go-m'*
 	  'm'	Menu bar is present.
 								*'go-M'*
@@ -3599,13 +3588,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 	'iconstring' (if it is not empty), or to the name of the file
 	currently being edited.  Only the last part of the name is used.
 	Overridden by the 'iconstring' option.
-	Only works if the terminal supports setting window icons (currently
+	Only works if the terminal supports setting window icons.
-	only X11 GUI and terminals with a non-empty 't_IS' option - this is
-	Unix xterm by default, where 't_IS' is taken from the builtin termcap).
-	When Vim was compiled with HAVE_X11 defined, the original icon will be
-	restored if possible |X11|.  See |X11-icon| for changing the icon on
-	X11.
-	For MS-Windows the icon can be changed, see |windows-icon|.
 
 						*'iconstring'*
 'iconstring'		string	(default "")
@@ -3615,10 +3598,6 @@ A jump table for the options with a short description can be found at |Q_op|.
 	When this option is not empty, it will be used for the icon text of
 	the window.  This happens only when the 'icon' option is on.
 	Only works if the terminal supports setting window icon text
-	(currently only X11 GUI and terminals with a non-empty 't_IS' option).
-	Does not work for MS Windows.
-	When Vim was compiled with HAVE_X11 defined, the original icon will be
-	restored if possible |X11|.
 	When this option contains printf-style '%' items, they will be
 	expanded according to the rules used for 'statusline'.  See
 	'titlestring' for example settings.
@@ -6646,20 +6625,6 @@ A jump table for the options with a short description can be found at |Q_op|.
 	(currently Win32 console, all GUI versions and terminals with a non-
 	empty 't_ts' option - this is Unix xterm by default, where 't_ts' is
 	taken from the builtin termcap).
-								*X11*
-	When Vim was compiled with HAVE_X11 defined, the original title will
-	be restored if possible.  The output of ":version" will include "+X11"
-	when HAVE_X11 was defined, otherwise it will be "-X11".  This also
-	works for the icon name |'icon'|.
-	But: When Vim was started with the |-X| argument, restoring the title
-	will not work (except in the GUI).
-	If the title cannot be restored, it is set to the value of 'titleold'.
-	You might want to restore the title outside of Vim then.
-	When using an xterm from a remote machine you can use this command:
-	    rsh machine_name xterm -display $DISPLAY &
-	then the WINDOWID environment variable should be inherited and the
-	title of the window should change back to what it should be after
-	exiting Vim.
 
 								*'titlelen'*
 'titlelen'		number	(default 85)
@@ -6696,17 +6661,15 @@ A jump table for the options with a short description can be found at |Q_op|.
 	Only works if the terminal supports setting window titles (currently
 	Win32 console, all GUI versions and terminals with a non-empty 't_ts'
 	option).
-	When Vim was compiled with HAVE_X11 defined, the original title will
-	be restored if possible |X11|.
 	When this option contains printf-style '%' items, they will be
 	expanded according to the rules used for 'statusline'.
 	Example: >
-    :auto BufEnter * let &titlestring = hostname() . "/" . expand("%:p")
+	    :auto BufEnter * let &titlestring = hostname() . "/" . expand("%:p")
-    :set title titlestring=%<%F%=%l/%L-%P titlelen=70
+	    :set title titlestring=%<%F%=%l/%L-%P titlelen=70
 <	The value of 'titlelen' is used to align items in the middle or right
 	of the available space.
 	Some people prefer to have the file name first: >
-    :set titlestring=%t%(\ %M%)%(\ (%{expand(\"%:~:.:h\")})%)%(\ %a%)
+	    :set titlestring=%t%(\ %M%)%(\ (%{expand(\"%:~:.:h\")})%)%(\ %a%)
 <	Note the use of "%{ }" and an expression to get the path of the file,
 	without the file name.  The "%( %)" constructs are used to add a
 	separating space only when needed.

runtime/doc/quickref.txt

@@ -1136,7 +1136,6 @@ Context-sensitive completion on the command-line:
 |-w|	-w {scriptout}	    write typed chars to file {scriptout} (append)
 |-W|	-W {scriptout}	    write typed chars to file {scriptout} (overwrite)
 |-u|	-u {vimrc}	    read inits from {vimrc} instead of other inits
-|-U|	-U {gvimrc}	    idem, for when starting the GUI
 |-i|	-i {viminfo}	    read info from {viminfo} instead of other files
 |---|	--		    end of options, other arguments are file names
 |--help|    --help	    show list of arguments and exit

runtime/doc/starting.txt

@@ -562,17 +562,12 @@ just like executing a command from a vimrc/exrc in the current directory.
 
 							*slow-start*
 If Vim takes a long time to start up, use the |--startuptime| argument to find
-out what happens.  There are a few common causes:
+out what happens.
-- If the Unix version was compiled with the GUI and/or X11 (check the output
+
-  of ":version" for "+GUI" and "+X11"), it may need to load shared libraries
+If you have "viminfo" enabled, the loading of the viminfo file may take a
-  and connect to the X11 server.  Try compiling a version with GUI and X11
+while.  You can find out if this is the problem by disabling viminfo for a
-  disabled.  This also should make the executable smaller.
+moment (use the Vim argument "-i NONE", |-i|).  Try reducing the number of
-  Use the |-X| command line argument to avoid connecting to the X server when
+lines stored in a register with ":set viminfo='20,<50,s10".  |viminfo-file|.
-  running in a terminal.
-- If you have "viminfo" enabled, the loading of the viminfo file may take a
-  while.  You can find out if this is the problem by disabling viminfo for a
-  moment (use the Vim argument "-i NONE", |-i|).  Try reducing the number of
-  lines stored in a register with ":set viminfo='20,<50,s10".  |viminfo-file|.
 
 							*:intro*
 When Vim starts without a file name, an introductory message is displayed (for

runtime/doc/term.txt

@@ -577,10 +577,6 @@ Shortcut: If the insert position is on the screen at the same time as the
 Visual text, you can do 2, 3 and 4 all in one: Click the middle mouse button
 at the insert position.
 
-Note: When the |-X| command line argument is used, Vim will not connect to the
-X server and copy/paste to the X clipboard (selection) will not work.  Use the
-shift key with the mouse buttons to let the xterm do the selection.
-
 							*xterm-command-server*
 When the X-server clipboard is available, the command server described in
 |x11-clientserver| can be enabled with the --servername command line argument.

runtime/doc/various.txt

@@ -413,7 +413,6 @@ m  *+xpm_w32*		Win32 GUI only: pixmap support |w32-xpm-support|
    *+xsmp_interact*	interactive XSMP (X session management) support
 N  *+xterm_clipboard*	Unix only: xterm clipboard handling
 m  *+xterm_save*	save and restore xterm screen |xterm-screens|
-N  *+X11*		Unix only: can restore window title |X11|
 
 							*/dyn* *E370* *E448*
 			To some of the features "/dyn" is added when the