diff --git a/gtk/theme/Adwaita/_common.scss b/gtk/theme/Adwaita/_common.scss
index 064a8d30a5..2526ccbe84 100644
--- a/gtk/theme/Adwaita/_common.scss
+++ b/gtk/theme/Adwaita/_common.scss
@@ -886,25 +886,13 @@ button {
   &.font { > box > box > label { font-weight: bold; }}
 
   // inline-toolbar buttons
-  .inline-toolbar &, .inline-toolbar &:backdrop {
-    border-radius: 2px;
-    border-width: 1px;
-    @extend %linked;
-  }
+  .inline-toolbar & { @extend %linked; }
 
   .primary-toolbar & { -gtk-icon-shadow: none; } // tango icons don't need shadows
 
-  .linked > &,
-  .linked > &:hover,
-  .linked > &:active,
-  .linked > &:checked,
-  .linked > &:backdrop { @extend %linked; }
+  .linked > & { @extend %linked; }
 
-  .linked.vertical > &,
-  .linked.vertical > &:hover,
-  .linked.vertical > &:active,
-  .linked.vertical > &:checked,
-  .linked.vertical > &:backdrop { @extend %linked_vertical; }
+  .linked.vertical > & { @extend %linked_vertical; }
 
   &.circular { // The Bloody Circul Button
     border-radius: 9999px;
@@ -1004,8 +992,7 @@ button {
 }
 
 // More inline toolbar buttons
-toolbar.inline-toolbar toolbutton,
-toolbar.inline-toolbar toolbutton:backdrop {
+toolbar.inline-toolbar toolbutton {
   > button.flat { @extend %linked_middle; }
 
   &:first-child > button.flat { @extend %linked_left; }
@@ -1016,38 +1003,29 @@ toolbar.inline-toolbar toolbutton:backdrop {
 }
 
 %linked_middle {
-  border-radius: 0;
   border-right-style: none;
+  border-radius: 0;
   -gtk-outline-radius: 0;
 }
 
 %linked_left {
     border-top-left-radius: $button_radius;
     border-bottom-left-radius: $button_radius;
-    border-top-right-radius: 0;
-    border-bottom-right-radius: 0;
-    border-right-style: none;
-    -gtk-outline-bottom-left-radius: $button_radius;
     -gtk-outline-top-left-radius: $button_radius;
-    -gtk-outline-top-right-radius: 0;
-    -gtk-outline-bottom-right-radius: 0;
+    -gtk-outline-bottom-left-radius: $button_radius;
 }
 
 %linked_right {
-    border-top-left-radius: 0;
-    border-bottom-left-radius: 0;
+    border-right-style: solid;
     border-top-right-radius: $button_radius;
     border-bottom-right-radius: $button_radius;
-    border-right-style: solid;
-    -gtk-outline-bottom-right-radius: $button_radius;
     -gtk-outline-top-right-radius: $button_radius;
-    -gtk-outline-bottom-left-radius: 0;
-    -gtk-outline-top-left-radius: 0;
+    -gtk-outline-bottom-right-radius: $button_radius;
 }
 
 %linked_only_child {
-    border-radius: $button_radius;
     border-style: solid;
+    border-radius: $button_radius;
     -gtk-outline-radius: $button_radius;
 }
 
@@ -1081,25 +1059,31 @@ toolbar.inline-toolbar toolbutton:backdrop {
 %linked_vertical_middle {
   border-style: solid solid none solid;
   border-radius: 0;
+  -gtk-outline-radius: 0;
 }
 
 %linked_vertical_top {
   border-top-left-radius: $button_radius;
   border-top-right-radius: $button_radius;
+  -gtk-outline-top-left-radius: $button_radius;
+  -gtk-outline-top-right-radius: $button_radius;
 }
 
 %linked_vertical_bottom {
+  border-bottom-style: solid;
   border-bottom-left-radius: $button_radius;
   border-bottom-right-radius: $button_radius;
-  border-style: solid;
+  -gtk-outline-bottom-left-radius: $button_radius;
+  -gtk-outline-bottom-right-radius: $button_radius;
 }
 
 %linked_vertical_only_child {
-  border-radius: $button_radius;
   border-style: solid;
+  border-radius: $button_radius;
+  -gtk-outline-radius: $button_radius;
 }
 
-%linked_vertical{
+%linked_vertical {
   @extend %linked_vertical_middle;
 
   &:first-child { @extend %linked_vertical_top; }
@@ -1471,21 +1455,17 @@ combobox {
   }
 }
 
-.linked > combobox > box > button.combo {
-  // the combo is a composite widget so the way we do button linking doesn't
-  // work, special case needed. See
-  // https://bugzilla.gnome.org/show_bug.cgi?id=733979
-
-  &:dir(ltr),
-  &:dir(rtl) { @extend %linked_middle; } // specificity bump
-}
+// the combo is a composite widget so the way we do button linking doesn't
+// work, special case needed. See
+// https://bugzilla.gnome.org/show_bug.cgi?id=733979
 
+.linked:not(.vertical) > combobox > box > button.combo { @extend %linked_middle; }
 .linked:not(.vertical) > combobox:first-child > box > button.combo { @extend %linked_left; }
 .linked:not(.vertical) > combobox:last-child > box > button.combo { @extend %linked_right; }
 .linked:not(.vertical) > combobox:only-child > box > button.combo { @extend %linked_only_child; }
 
 .linked.vertical > combobox > box > button.combo { @extend %linked_vertical_middle; }
-.linked.vertical > combobox:first-child > box > button.combo { @extend %linked_vertical_top;}
+.linked.vertical > combobox:first-child > box > button.combo { @extend %linked_vertical_top; }
 .linked.vertical > combobox:last-child > box > button.combo { @extend %linked_vertical_bottom; }
 .linked.vertical > combobox:only-child > box > button.combo { @extend %linked_vertical_only_child; }
 
@@ -3993,36 +3973,20 @@ messagedialog { // Message Dialog styling
 
     .dialog-action-area button {
       padding: 10px 14px; // labels are not vertically centered on message dialog, this is a workaround
-      border-radius: 0;
-      border-left-style: solid;
       border-right-style: none;
       border-bottom-style: none;
+      border-radius: 0;
+      -gtk-outline-radius: 0;
 
-      &:first-child:not(:only-child) {
+      &:first-child {
         border-left-style: none;
         border-bottom-left-radius: $button_radius + 2;
         -gtk-outline-bottom-left-radius: $button_radius + 2;
-        -gtk-outline-top-left-radius: 0px;
-        -gtk-outline-top-right-radius: 0px;
-        -gtk-outline-bottom-right-radius: 0px;
       }
-  
-      &:last-child:not(:only-child) {
+
+      &:last-child {
         border-bottom-right-radius: $button_radius + 2;
         -gtk-outline-bottom-right-radius: $button_radius + 2;
-        -gtk-outline-top-right-radius: 0px;
-        -gtk-outline-bottom-left-radius: 0px;
-        -gtk-outline-top-left-radius: 0px;
-      }
-      &:only-child {
-        border-top-right-radius: 0;
-        border-top-left-radius: 0;
-        border-bottom-left-radius: $button_radius + 2;
-        border-bottom-right-radius: $button_radius + 2;
-        -gtk-outline-top-right-radius: 0px;
-        -gtk-outline-top-left-radius: 0px;
-        -gtk-outline-bottom-left-radius: $button_radius + 2;
-        -gtk-outline-bottom-right-radius: $button_radius + 2;
       }
     }
   }
diff --git a/gtk/theme/Adwaita/gtk-contained-dark.css b/gtk/theme/Adwaita/gtk-contained-dark.css
index f9f29bee6b..e5cd294a33 100644
--- a/gtk/theme/Adwaita/gtk-contained-dark.css
+++ b/gtk/theme/Adwaita/gtk-contained-dark.css
@@ -356,8 +356,6 @@ button.font separator, button.file separator { background-color: transparent; }
 
 button.font > box > box > label { font-weight: bold; }
 
-.inline-toolbar button, .inline-toolbar button:backdrop { border-radius: 2px; border-width: 1px; }
-
 .primary-toolbar button { -gtk-icon-shadow: none; }
 
 button.circular { border-radius: 9999px; -gtk-outline-radius: 9999px; padding: 4px; /* circles instead of ellipses */ background-origin: padding-box, border-box; background-clip: padding-box, border-box; }
@@ -392,21 +390,21 @@ stacksidebar row.needs-attention > label:dir(rtl), .stack-switcher > button.need
 
 .inline-toolbar toolbutton > button:backdrop:disabled:active, .inline-toolbar toolbutton > button:backdrop:disabled:checked { color: #5b5b5b; border-color: #202020; background-image: image(#2a2a2a); box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
 
-.linked > combobox > box > button.combo:dir(ltr), .linked > combobox > box > button.combo:dir(rtl), filechooser .path-bar.linked > button, .linked:not(.vertical) > spinbutton:not(.vertical), .linked:not(.vertical) > entry, .inline-toolbar button, .inline-toolbar button:backdrop, .linked > button, .linked > button:hover, .linked > button:active, .linked > button:checked, .linked > button:backdrop, toolbar.inline-toolbar toolbutton > button.flat, toolbar.inline-toolbar toolbutton:backdrop > button.flat { border-radius: 0; border-right-style: none; -gtk-outline-radius: 0; }
+.linked:not(.vertical) > combobox > box > button.combo, filechooser .path-bar.linked > button, .linked:not(.vertical) > spinbutton:not(.vertical), .linked:not(.vertical) > entry, .inline-toolbar button, .linked > button, toolbar.inline-toolbar toolbutton > button.flat { border-right-style: none; border-radius: 0; -gtk-outline-radius: 0; }
 
-.linked:not(.vertical) > combobox:first-child > box > button.combo, combobox.linked button:nth-child(2):dir(rtl), filechooser .path-bar.linked > button:dir(rtl):last-child, filechooser .path-bar.linked > button:dir(ltr):first-child, .linked:not(.vertical) > spinbutton:first-child:not(.vertical), .linked:not(.vertical) > entry:first-child, .inline-toolbar button:first-child, .inline-toolbar button:first-child:backdrop, .linked > button:first-child, .linked > button:first-child:hover, .linked > button:first-child:active, .linked > button:first-child:checked, .linked > button:first-child:backdrop, toolbar.inline-toolbar toolbutton:first-child > button.flat { border-top-left-radius: 5px; border-bottom-left-radius: 5px; border-top-right-radius: 0; border-bottom-right-radius: 0; border-right-style: none; -gtk-outline-bottom-left-radius: 5px; -gtk-outline-top-left-radius: 5px; -gtk-outline-top-right-radius: 0; -gtk-outline-bottom-right-radius: 0; }
+.linked:not(.vertical) > combobox:first-child > box > button.combo, combobox.linked button:nth-child(2):dir(rtl), filechooser .path-bar.linked > button:dir(rtl):last-child, filechooser .path-bar.linked > button:dir(ltr):first-child, .linked:not(.vertical) > spinbutton:first-child:not(.vertical), .linked:not(.vertical) > entry:first-child, .inline-toolbar button:first-child, .linked > button:first-child, toolbar.inline-toolbar toolbutton:first-child > button.flat { border-top-left-radius: 5px; border-bottom-left-radius: 5px; -gtk-outline-top-left-radius: 5px; -gtk-outline-bottom-left-radius: 5px; }
 
-.linked:not(.vertical) > combobox:last-child > box > button.combo, combobox.linked button:nth-child(2):dir(ltr), filechooser .path-bar.linked > button:dir(rtl):first-child, filechooser .path-bar.linked > button:dir(ltr):last-child, .linked:not(.vertical) > spinbutton:last-child:not(.vertical), .linked:not(.vertical) > entry:last-child, .inline-toolbar button:last-child, .inline-toolbar button:last-child:backdrop, .linked > button:last-child, .linked > button:last-child:hover, .linked > button:last-child:active, .linked > button:last-child:checked, .linked > button:last-child:backdrop, toolbar.inline-toolbar toolbutton:last-child > button.flat { border-top-left-radius: 0; border-bottom-left-radius: 0; border-top-right-radius: 5px; border-bottom-right-radius: 5px; border-right-style: solid; -gtk-outline-bottom-right-radius: 5px; -gtk-outline-top-right-radius: 5px; -gtk-outline-bottom-left-radius: 0; -gtk-outline-top-left-radius: 0; }
+.linked:not(.vertical) > combobox:last-child > box > button.combo, combobox.linked button:nth-child(2):dir(ltr), filechooser .path-bar.linked > button:dir(rtl):first-child, filechooser .path-bar.linked > button:dir(ltr):last-child, .linked:not(.vertical) > spinbutton:last-child:not(.vertical), .linked:not(.vertical) > entry:last-child, .inline-toolbar button:last-child, .linked > button:last-child, toolbar.inline-toolbar toolbutton:last-child > button.flat { border-right-style: solid; border-top-right-radius: 5px; border-bottom-right-radius: 5px; -gtk-outline-top-right-radius: 5px; -gtk-outline-bottom-right-radius: 5px; }
 
-.linked:not(.vertical) > combobox:only-child > box > button.combo, filechooser .path-bar.linked > button:only-child, .linked:not(.vertical) > spinbutton:only-child:not(.vertical), .linked:not(.vertical) > entry:only-child, .inline-toolbar button:only-child, .inline-toolbar button:only-child:backdrop, .linked > button:only-child, .linked > button:only-child:hover, .linked > button:only-child:active, .linked > button:only-child:checked, .linked > button:only-child:backdrop, toolbar.inline-toolbar toolbutton:only-child > button.flat { border-radius: 5px; border-style: solid; -gtk-outline-radius: 5px; }
+.linked:not(.vertical) > combobox:only-child > box > button.combo, filechooser .path-bar.linked > button:only-child, .linked:not(.vertical) > spinbutton:only-child:not(.vertical), .linked:not(.vertical) > entry:only-child, .inline-toolbar button:only-child, .linked > button:only-child, toolbar.inline-toolbar toolbutton:only-child > button.flat { border-style: solid; border-radius: 5px; -gtk-outline-radius: 5px; }
 
-.linked.vertical > combobox > box > button.combo, .linked.vertical > spinbutton:not(.vertical), .linked.vertical > entry, .linked.vertical > button, .linked.vertical > button:hover, .linked.vertical > button:active, .linked.vertical > button:checked, .linked.vertical > button:backdrop { border-style: solid solid none solid; border-radius: 0; }
+.linked.vertical > combobox > box > button.combo, .linked.vertical > spinbutton:not(.vertical), .linked.vertical > entry, .linked.vertical > button { border-style: solid solid none solid; border-radius: 0; -gtk-outline-radius: 0; }
 
-.linked.vertical > combobox:first-child > box > button.combo, .linked.vertical > spinbutton:first-child:not(.vertical), .linked.vertical > entry:first-child, .linked.vertical > button:first-child, .linked.vertical > button:first-child:hover, .linked.vertical > button:first-child:active, .linked.vertical > button:first-child:checked, .linked.vertical > button:first-child:backdrop { border-top-left-radius: 5px; border-top-right-radius: 5px; }
+.linked.vertical > combobox:first-child > box > button.combo, .linked.vertical > spinbutton:first-child:not(.vertical), .linked.vertical > entry:first-child, .linked.vertical > button:first-child { border-top-left-radius: 5px; border-top-right-radius: 5px; -gtk-outline-top-left-radius: 5px; -gtk-outline-top-right-radius: 5px; }
 
-.linked.vertical > combobox:last-child > box > button.combo, .linked.vertical > spinbutton:last-child:not(.vertical), .linked.vertical > entry:last-child, .linked.vertical > button:last-child, .linked.vertical > button:last-child:hover, .linked.vertical > button:last-child:active, .linked.vertical > button:last-child:checked, .linked.vertical > button:last-child:backdrop { border-bottom-left-radius: 5px; border-bottom-right-radius: 5px; border-style: solid; }
+.linked.vertical > combobox:last-child > box > button.combo, .linked.vertical > spinbutton:last-child:not(.vertical), .linked.vertical > entry:last-child, .linked.vertical > button:last-child { border-bottom-style: solid; border-bottom-left-radius: 5px; border-bottom-right-radius: 5px; -gtk-outline-bottom-left-radius: 5px; -gtk-outline-bottom-right-radius: 5px; }
 
-.linked.vertical > combobox:only-child > box > button.combo, .linked.vertical > spinbutton:only-child:not(.vertical), .linked.vertical > entry:only-child, .linked.vertical > button:only-child, .linked.vertical > button:only-child:hover, .linked.vertical > button:only-child:active, .linked.vertical > button:only-child:checked, .linked.vertical > button:only-child:backdrop { border-radius: 5px; border-style: solid; }
+.linked.vertical > combobox:only-child > box > button.combo, .linked.vertical > spinbutton:only-child:not(.vertical), .linked.vertical > entry:only-child, .linked.vertical > button:only-child { border-style: solid; border-radius: 5px; -gtk-outline-radius: 5px; }
 
 .scale-popup button:backdrop:hover, .scale-popup button:backdrop:disabled, .scale-popup button:backdrop, .scale-popup button:hover, calendar.button, button:link:hover, button:link:active, button:link:checked, button:visited:hover, button:visited:active, button:visited:checked, button:link, button:visited, list row button.image-button:not(.flat), modelbutton.flat:backdrop, modelbutton.flat:backdrop:hover, modelbutton.flat, .menuitem.button.flat { background-color: transparent; background-image: none; border-color: transparent; box-shadow: inset 0 1px rgba(255, 255, 255, 0), 0 1px rgba(255, 255, 255, 0); text-shadow: none; -gtk-icon-shadow: none; }
 
@@ -1596,13 +1594,11 @@ messagedialog .titlebar { min-height: 20px; background-image: none; background-c
 
 messagedialog.csd.background { border-bottom-left-radius: 9px; border-bottom-right-radius: 9px; }
 
-messagedialog.csd .dialog-action-area button { padding: 10px 14px; border-radius: 0; border-left-style: solid; border-right-style: none; border-bottom-style: none; }
+messagedialog.csd .dialog-action-area button { padding: 10px 14px; border-right-style: none; border-bottom-style: none; border-radius: 0; -gtk-outline-radius: 0; }
 
-messagedialog.csd .dialog-action-area button:first-child:not(:only-child) { border-left-style: none; border-bottom-left-radius: 7px; -gtk-outline-bottom-left-radius: 7px; -gtk-outline-top-left-radius: 0px; -gtk-outline-top-right-radius: 0px; -gtk-outline-bottom-right-radius: 0px; }
+messagedialog.csd .dialog-action-area button:first-child { border-left-style: none; border-bottom-left-radius: 7px; -gtk-outline-bottom-left-radius: 7px; }
 
-messagedialog.csd .dialog-action-area button:last-child:not(:only-child) { border-bottom-right-radius: 7px; -gtk-outline-bottom-right-radius: 7px; -gtk-outline-top-right-radius: 0px; -gtk-outline-bottom-left-radius: 0px; -gtk-outline-top-left-radius: 0px; }
-
-messagedialog.csd .dialog-action-area button:only-child { border-top-right-radius: 0; border-top-left-radius: 0; border-bottom-left-radius: 7px; border-bottom-right-radius: 7px; -gtk-outline-top-right-radius: 0px; -gtk-outline-top-left-radius: 0px; -gtk-outline-bottom-left-radius: 7px; -gtk-outline-bottom-right-radius: 7px; }
+messagedialog.csd .dialog-action-area button:last-child { border-bottom-right-radius: 7px; -gtk-outline-bottom-right-radius: 7px; }
 
 filechooser .dialog-action-box { border-top: 1px solid #1b1b1b; }
 
diff --git a/gtk/theme/Adwaita/gtk-contained.css b/gtk/theme/Adwaita/gtk-contained.css
index 92adbdbb8b..591ffb6255 100644
--- a/gtk/theme/Adwaita/gtk-contained.css
+++ b/gtk/theme/Adwaita/gtk-contained.css
@@ -358,8 +358,6 @@ button.font separator, button.file separator { background-color: transparent; }
 
 button.font > box > box > label { font-weight: bold; }
 
-.inline-toolbar button, .inline-toolbar button:backdrop { border-radius: 2px; border-width: 1px; }
-
 .primary-toolbar button { -gtk-icon-shadow: none; }
 
 button.circular { border-radius: 9999px; -gtk-outline-radius: 9999px; padding: 4px; /* circles instead of ellipses */ background-origin: padding-box, border-box; background-clip: padding-box, border-box; }
@@ -394,21 +392,21 @@ stacksidebar row.needs-attention > label:dir(rtl), .stack-switcher > button.need
 
 .inline-toolbar toolbutton > button:backdrop:disabled:active, .inline-toolbar toolbutton > button:backdrop:disabled:checked { color: #d4cfca; border-color: #d5d0cc; background-image: image(#e4e4e0); box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
 
-.linked > combobox > box > button.combo:dir(ltr), .linked > combobox > box > button.combo:dir(rtl), filechooser .path-bar.linked > button, .linked:not(.vertical) > spinbutton:not(.vertical), .linked:not(.vertical) > entry, .inline-toolbar button, .inline-toolbar button:backdrop, .linked > button, .linked > button:hover, .linked > button:active, .linked > button:checked, .linked > button:backdrop, toolbar.inline-toolbar toolbutton > button.flat, toolbar.inline-toolbar toolbutton:backdrop > button.flat { border-radius: 0; border-right-style: none; -gtk-outline-radius: 0; }
+.linked:not(.vertical) > combobox > box > button.combo, filechooser .path-bar.linked > button, .linked:not(.vertical) > spinbutton:not(.vertical), .linked:not(.vertical) > entry, .inline-toolbar button, .linked > button, toolbar.inline-toolbar toolbutton > button.flat { border-right-style: none; border-radius: 0; -gtk-outline-radius: 0; }
 
-.linked:not(.vertical) > combobox:first-child > box > button.combo, combobox.linked button:nth-child(2):dir(rtl), filechooser .path-bar.linked > button:dir(rtl):last-child, filechooser .path-bar.linked > button:dir(ltr):first-child, .linked:not(.vertical) > spinbutton:first-child:not(.vertical), .linked:not(.vertical) > entry:first-child, .inline-toolbar button:first-child, .inline-toolbar button:first-child:backdrop, .linked > button:first-child, .linked > button:first-child:hover, .linked > button:first-child:active, .linked > button:first-child:checked, .linked > button:first-child:backdrop, toolbar.inline-toolbar toolbutton:first-child > button.flat { border-top-left-radius: 5px; border-bottom-left-radius: 5px; border-top-right-radius: 0; border-bottom-right-radius: 0; border-right-style: none; -gtk-outline-bottom-left-radius: 5px; -gtk-outline-top-left-radius: 5px; -gtk-outline-top-right-radius: 0; -gtk-outline-bottom-right-radius: 0; }
+.linked:not(.vertical) > combobox:first-child > box > button.combo, combobox.linked button:nth-child(2):dir(rtl), filechooser .path-bar.linked > button:dir(rtl):last-child, filechooser .path-bar.linked > button:dir(ltr):first-child, .linked:not(.vertical) > spinbutton:first-child:not(.vertical), .linked:not(.vertical) > entry:first-child, .inline-toolbar button:first-child, .linked > button:first-child, toolbar.inline-toolbar toolbutton:first-child > button.flat { border-top-left-radius: 5px; border-bottom-left-radius: 5px; -gtk-outline-top-left-radius: 5px; -gtk-outline-bottom-left-radius: 5px; }
 
-.linked:not(.vertical) > combobox:last-child > box > button.combo, combobox.linked button:nth-child(2):dir(ltr), filechooser .path-bar.linked > button:dir(rtl):first-child, filechooser .path-bar.linked > button:dir(ltr):last-child, .linked:not(.vertical) > spinbutton:last-child:not(.vertical), .linked:not(.vertical) > entry:last-child, .inline-toolbar button:last-child, .inline-toolbar button:last-child:backdrop, .linked > button:last-child, .linked > button:last-child:hover, .linked > button:last-child:active, .linked > button:last-child:checked, .linked > button:last-child:backdrop, toolbar.inline-toolbar toolbutton:last-child > button.flat { border-top-left-radius: 0; border-bottom-left-radius: 0; border-top-right-radius: 5px; border-bottom-right-radius: 5px; border-right-style: solid; -gtk-outline-bottom-right-radius: 5px; -gtk-outline-top-right-radius: 5px; -gtk-outline-bottom-left-radius: 0; -gtk-outline-top-left-radius: 0; }
+.linked:not(.vertical) > combobox:last-child > box > button.combo, combobox.linked button:nth-child(2):dir(ltr), filechooser .path-bar.linked > button:dir(rtl):first-child, filechooser .path-bar.linked > button:dir(ltr):last-child, .linked:not(.vertical) > spinbutton:last-child:not(.vertical), .linked:not(.vertical) > entry:last-child, .inline-toolbar button:last-child, .linked > button:last-child, toolbar.inline-toolbar toolbutton:last-child > button.flat { border-right-style: solid; border-top-right-radius: 5px; border-bottom-right-radius: 5px; -gtk-outline-top-right-radius: 5px; -gtk-outline-bottom-right-radius: 5px; }
 
-.linked:not(.vertical) > combobox:only-child > box > button.combo, filechooser .path-bar.linked > button:only-child, .linked:not(.vertical) > spinbutton:only-child:not(.vertical), .linked:not(.vertical) > entry:only-child, .inline-toolbar button:only-child, .inline-toolbar button:only-child:backdrop, .linked > button:only-child, .linked > button:only-child:hover, .linked > button:only-child:active, .linked > button:only-child:checked, .linked > button:only-child:backdrop, toolbar.inline-toolbar toolbutton:only-child > button.flat { border-radius: 5px; border-style: solid; -gtk-outline-radius: 5px; }
+.linked:not(.vertical) > combobox:only-child > box > button.combo, filechooser .path-bar.linked > button:only-child, .linked:not(.vertical) > spinbutton:only-child:not(.vertical), .linked:not(.vertical) > entry:only-child, .inline-toolbar button:only-child, .linked > button:only-child, toolbar.inline-toolbar toolbutton:only-child > button.flat { border-style: solid; border-radius: 5px; -gtk-outline-radius: 5px; }
 
-.linked.vertical > combobox > box > button.combo, .linked.vertical > spinbutton:not(.vertical), .linked.vertical > entry, .linked.vertical > button, .linked.vertical > button:hover, .linked.vertical > button:active, .linked.vertical > button:checked, .linked.vertical > button:backdrop { border-style: solid solid none solid; border-radius: 0; }
+.linked.vertical > combobox > box > button.combo, .linked.vertical > spinbutton:not(.vertical), .linked.vertical > entry, .linked.vertical > button { border-style: solid solid none solid; border-radius: 0; -gtk-outline-radius: 0; }
 
-.linked.vertical > combobox:first-child > box > button.combo, .linked.vertical > spinbutton:first-child:not(.vertical), .linked.vertical > entry:first-child, .linked.vertical > button:first-child, .linked.vertical > button:first-child:hover, .linked.vertical > button:first-child:active, .linked.vertical > button:first-child:checked, .linked.vertical > button:first-child:backdrop { border-top-left-radius: 5px; border-top-right-radius: 5px; }
+.linked.vertical > combobox:first-child > box > button.combo, .linked.vertical > spinbutton:first-child:not(.vertical), .linked.vertical > entry:first-child, .linked.vertical > button:first-child { border-top-left-radius: 5px; border-top-right-radius: 5px; -gtk-outline-top-left-radius: 5px; -gtk-outline-top-right-radius: 5px; }
 
-.linked.vertical > combobox:last-child > box > button.combo, .linked.vertical > spinbutton:last-child:not(.vertical), .linked.vertical > entry:last-child, .linked.vertical > button:last-child, .linked.vertical > button:last-child:hover, .linked.vertical > button:last-child:active, .linked.vertical > button:last-child:checked, .linked.vertical > button:last-child:backdrop { border-bottom-left-radius: 5px; border-bottom-right-radius: 5px; border-style: solid; }
+.linked.vertical > combobox:last-child > box > button.combo, .linked.vertical > spinbutton:last-child:not(.vertical), .linked.vertical > entry:last-child, .linked.vertical > button:last-child { border-bottom-style: solid; border-bottom-left-radius: 5px; border-bottom-right-radius: 5px; -gtk-outline-bottom-left-radius: 5px; -gtk-outline-bottom-right-radius: 5px; }
 
-.linked.vertical > combobox:only-child > box > button.combo, .linked.vertical > spinbutton:only-child:not(.vertical), .linked.vertical > entry:only-child, .linked.vertical > button:only-child, .linked.vertical > button:only-child:hover, .linked.vertical > button:only-child:active, .linked.vertical > button:only-child:checked, .linked.vertical > button:only-child:backdrop { border-radius: 5px; border-style: solid; }
+.linked.vertical > combobox:only-child > box > button.combo, .linked.vertical > spinbutton:only-child:not(.vertical), .linked.vertical > entry:only-child, .linked.vertical > button:only-child { border-style: solid; border-radius: 5px; -gtk-outline-radius: 5px; }
 
 .scale-popup button:backdrop:hover, .scale-popup button:backdrop:disabled, .scale-popup button:backdrop, .scale-popup button:hover, calendar.button, button:link:hover, button:link:active, button:link:checked, button:visited:hover, button:visited:active, button:visited:checked, button:link, button:visited, list row button.image-button:not(.flat), modelbutton.flat:backdrop, modelbutton.flat:backdrop:hover, modelbutton.flat, .menuitem.button.flat { background-color: transparent; background-image: none; border-color: transparent; box-shadow: inset 0 1px rgba(255, 255, 255, 0), 0 1px rgba(255, 255, 255, 0); text-shadow: none; -gtk-icon-shadow: none; }
 
@@ -1612,13 +1610,11 @@ messagedialog .titlebar { min-height: 20px; background-image: none; background-c
 
 messagedialog.csd.background { border-bottom-left-radius: 9px; border-bottom-right-radius: 9px; }
 
-messagedialog.csd .dialog-action-area button { padding: 10px 14px; border-radius: 0; border-left-style: solid; border-right-style: none; border-bottom-style: none; }
+messagedialog.csd .dialog-action-area button { padding: 10px 14px; border-right-style: none; border-bottom-style: none; border-radius: 0; -gtk-outline-radius: 0; }
 
-messagedialog.csd .dialog-action-area button:first-child:not(:only-child) { border-left-style: none; border-bottom-left-radius: 7px; -gtk-outline-bottom-left-radius: 7px; -gtk-outline-top-left-radius: 0px; -gtk-outline-top-right-radius: 0px; -gtk-outline-bottom-right-radius: 0px; }
+messagedialog.csd .dialog-action-area button:first-child { border-left-style: none; border-bottom-left-radius: 7px; -gtk-outline-bottom-left-radius: 7px; }
 
-messagedialog.csd .dialog-action-area button:last-child:not(:only-child) { border-bottom-right-radius: 7px; -gtk-outline-bottom-right-radius: 7px; -gtk-outline-top-right-radius: 0px; -gtk-outline-bottom-left-radius: 0px; -gtk-outline-top-left-radius: 0px; }
-
-messagedialog.csd .dialog-action-area button:only-child { border-top-right-radius: 0; border-top-left-radius: 0; border-bottom-left-radius: 7px; border-bottom-right-radius: 7px; -gtk-outline-top-right-radius: 0px; -gtk-outline-top-left-radius: 0px; -gtk-outline-bottom-left-radius: 7px; -gtk-outline-bottom-right-radius: 7px; }
+messagedialog.csd .dialog-action-area button:last-child { border-bottom-right-radius: 7px; -gtk-outline-bottom-right-radius: 7px; }
 
 filechooser .dialog-action-box { border-top: 1px solid #cdc7c2; }