GTK toolbar button icon sizes are inconsistent on my Linux KDE system.  This causes the toolbar height to change when the buttons change.  In addition to being visually annoying, the bouncing effect causes a mouse click to turn into a drag event if the click causes the toolbar buttons to change.

See the attached animated gif for an example of the inconsistency.

Also see bug#56607.


In GNU Emacs 29.0.50 (build 3, x86_64-pc-linux-gnu, GTK+ Version 3.24.20, cairo version 1.16.0)
  of 2022-07-17 built on sprinkles
Repository revision: 81a39987224989774a3f14b70e78cc36722175c5
Repository branch: info-mode
System Description: Ubuntu 20.04.4 LTS

Configured using:
  'configure --with-modules=yes --with-x=yes --with-x-toolkit=gtk3
  --with-xwidgets=yes --with-pgtk --enable-checking=yes,glyphs
  --enable-check-lisp-object-type 'CFLAGS=-O0 -g3''

Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GPM GSETTINGS HARFBUZZ JPEG
JSON LCMS2 LIBOTF LIBSELINUX LIBSYSTEMD LIBXML2 MODULES NOTIFY INOTIFY
PDUMPER PGTK PNG RSVG SECCOMP SOUND SQLITE3 THREADS TIFF
TOOLKIT_SCROLL_BARS XIM XWIDGETS GTK3 ZLIB

Important settings:
   value of $LC_MONETARY: en_US.UTF-8
   value of $LC_NUMERIC: en_US.UTF-8
   value of $LC_TIME: root.UTF-8
   value of $LANG: en_US.UTF-8
   value of $XMODIFIERS: @im=ibus
   locale-coding-system: utf-8-unix

Major mode: Lisp Interaction

Minor modes in effect:
   tooltip-mode: t
   global-eldoc-mode: t
   eldoc-mode: t
   show-paren-mode: t
   electric-indent-mode: t
   mouse-wheel-mode: t
   tool-bar-mode: t
   menu-bar-mode: t
   file-name-shadow-mode: t
   global-font-lock-mode: t
   font-lock-mode: t
   blink-cursor-mode: t
   line-number-mode: t
   indent-tabs-mode: t
   transient-mark-mode: t
   auto-composition-mode: t
   auto-encryption-mode: t
   auto-compression-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message mailcap yank-media puny dired
dired-loaddefs rfc822 mml mml-sec password-cache epa derived epg rfc6068
epg-config gnus-util text-property-search time-date subr-x mm-decode
mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader
cl-loaddefs cl-lib sendmail rfc2047 rfc2045 ietf-drums mm-util
mail-prsvr mail-utils rmc iso-transl tooltip eldoc paren electric
uniquify ediff-hook vc-hooks lisp-float-type elisp-mode mwheel
term/pgtk-win pgtk-win term/common-win pgtk-dnd tool-bar dnd fontset
image regexp-opt fringe tabulated-list replace newcomment text-mode
lisp-mode prog-mode register page tab-bar menu-bar rfn-eshadow isearch
easymenu timer select scroll-bar mouse jit-lock font-lock syntax
font-core term/tty-colors frame minibuffer nadvice seq simple cl-generic
indonesian philippine cham georgian utf-8-lang misc-lang vietnamese
tibetan thai tai-viet lao korean japanese eucjp-ms cp51932 hebrew greek
romanian slovak czech european ethiopic indian cyrillic chinese
composite emoji-zwj charscript charprop case-table epa-hook
jka-cmpr-hook help abbrev obarray oclosure cl-preloaded button loaddefs
faces cus-face macroexp files window text-properties overlay sha1 md5
base64 format env code-pages mule custom widget keymap
hashtable-print-readable backquote threads xwidget-internal dbusbind
inotify dynamic-setting system-font-setting font-render-setting cairo
gtk pgtk lcms2 multi-tty make-network-process emacs)

Memory information:
((conses 16 35569 9757)
  (symbols 48 5067 0)
  (strings 32 13278 1788)
  (string-bytes 1 427136)
  (vectors 16 9165)
  (vector-slots 8 145065 15347)
  (floats 8 21 23)
  (intervals 56 210 0)
  (buffers 992 10))