[gtk] (48 commits) ...Merge branch 'wip/baedert/for-master' into 'master'

[Matthias Clasen <matthiasc src gnome org>]

Summary of changes:

  620388a... gtk4-demo: Add background to CSS Basics demo (*)
  e970c69... gsk: Fix border node diff implementation (*)
  ea21e50... testadjustsize: Fix overlay/box confusion (*)
  acbb59b... button: Whitespace (*)
  1d6ac9b... button: Use gtk_widget_class_add_shortcut directly (*)
  0fd8a28... spinbutton: Whitespace (*)
  53eed09... gdkcairoprivate: Fix header guard (*)
  21e2c7f... icon-browser: Add .navigation-sidebar to sidebar (*)
  2bff84c... gl: Adjust blur radius_multiplier (*)
  7a8d711... testoutsetshadowdrawing: Make window background white (*)
  c1c2205... gl renderer: Adjust gaussian blur sigma (*)
  b0d89b1... wayland: Fix a GSettingsSchema leak (*)
  51b398b... rendernodes: Whitespace (*)
  1375fb4... Change button hierarchy (*)
  af15583... fontchooser: Fix radio groups for features (*)
  830b2b7... printdialog: Fix radio groups (*)
  d3042da... printdialog: Make collate image smaller (*)
  e21b6a5... widget-factory: Fix up radio buttons (*)
  7a05381... gtk-demo: Port to font explorer to grouped checkbuttons (*)
  c9eb497... gtk-demo: Fix up the fontrendering demo (*)
  151b9c7... printeroptionwidget: Stop using radio buttons (*)
  d6e1276... mountoperation: Stop using radio buttons (*)
  2d6c43b... checkbutton: Drop gtkradiobutton.h include (*)
  00124b5... inspector: Drop gtkradiobutton.h include (*)
  33b65d5... stackswitcher: Drop gtkradiobutton.h include (*)
  f30d32f... pagesetupdialog: Drop gtkradiobutton.h include (*)
  591b525... checkbutton: Fix clicking on the last group member (*)
  cd284da... checkbutton: Reuse a helper function (*)
  1b6f734... tests: Stop using radio buttons (*)
  8f1bf59... Drop a long-dead test (*)
  ba6070b... build: The doc shooter works without x11 now (*)
  238d524... doc shooter: Drop radio buttons (*)
  cfade23... docs: Update the gallery image for check buttons (*)
  2c5c938... Clean up uses of gtk_toggle_button_get/set_active (*)
  c7b6c2f... Remove GtkRadioButton references in the docs (*)
  b69e8d8... Remove GtkRadioButton uses in ui files in tests (*)
  28d7f49... togglebutton: Add grouping (*)
  f085ac8... fontrendering demo: Stop using radio buttons (*)
  1125a43... iconbrowser: Stop using radio buttons (*)
  b98352d... widget-factory: Stop using radio buttons (*)
  bb6045f... builder-tool: Replace radio buttons by check buttons (*)
  17c4838... Drop GtkRadioButton (*)
  cff211e... migration guide: Mention button hierarchy changes (*)
  6ccc6a5... doc shooter: Remove radio button remnants (*)
  03dd629... Fix up the focus-chain tests (*)
  501cf49... Fix a typo (*)
  76b5ff6... pagesetupdialog: Just use labels in check buttons (*)
  ccb447d... Merge branch 'wip/baedert/for-master' into 'master'

(*) This commit already existed in another branch; no separate mail sent