code cleanup: deprecate bunch of old styles

These all have either better replacements or can be done without the style

chrome/deprecated/hide_tabs_toolbar_w_alltabs_button.css

@@ -0,0 +1,48 @@
+/* Source file https://github.com/MrOtherGuy/firefox-csshacks/tree/master/chrome/hide_tabs_toolbar_w_with_alltabs_button.css made available under Mozilla Public License v. 2.0
+See the above repository for updates as well as full license text. */
+
+/* This is less flexible than hide_tabs_toolbar.css, but this method aims to preserve the alltabs button and show it and window controls next to the main menu button */
+
+/* Load window_control_placeholder_support.css before this stylesheet */
+.tabbrowser-tab{
+  -moz-window-dragging: unset !important;
+}
+:root:not([customizing]) #tabbrowser-arrowscrollbox-periphery{
+  display: none;
+}
+#tabbrowser-tabs{ visibility: hidden;}
+#TabsToolbar-customization-target{
+  justify-content: flex-end;
+}
+#alltabs-button{
+  position: relative;
+  z-index: 1;
+  padding-bottom: 5px !important;
+  display: flex !important;
+  margin-right: 36px !important;
+}
+:root[sizemode="fullscreen"] #alltabs-button{ margin-right: calc(var(--uc-window-control-width) + 36px) !important }
+
+#TabsToolbar:not([inFullscreen]) > .titlebar-buttonbox-container{
+  padding-bottom: 5px;
+}
+#nav-bar{ padding-right: 40px !important; }
+/* Rules for window controls on left layout */
+@media (-moz-bool-pref: "userchrome.force-window-controls-on-left.enabled"),
+       (-moz-gtk-csd-reversed-placement),
+       (-moz-platform: macos){
+  #alltabs-button{
+    margin-right: var(--uc-window-drag-space-pre) !important;
+  }
+  :root[sizemode="fullscreen"] #alltabs-button{ margin-right: 0px !important; }
+}
+
+#TabsToolbar > .titlebar-spacer{ display: none }
+#TabsToolbar:not([customizing]){ margin-bottom: calc(0px - var(--tab-min-height) - 2 * var(--tab-block-margin))}
+
+#titlebar{
+  -moz-appearance: none !important;
+  will-change: unset !important;
+  transition: none !important;
+  opacity: 1 !important;
+}