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+/***
+Name: Sofia's userChrome.css
+Author: Sofia Aritz
+Website: https://sofiaritz.com
+Repository: https://git.sofiaritz.com/sofia/userChrome
+Last updated: 18/08/2023 (DD/MM/YYYY)
+
+Based on userChrome.org's Proton UI guide <https://www.userchrome.org/firefox-89-styling-proton-ui.html>
+with tweaks to the spacing of drop-down menus, sizing of the tabs, and the margins and paddings of the bookmarks.
+
+***/
+
+/*** Tighten up drop-down/context/popup menu spacing (8 Sep 2021) ***/
+
+menupopup:not(.in-menulist) > menuitem, 
+menupopup:not(.in-menulist) > menu {
+  padding-block: 6px !important; /* reduce to 3px, 2px, 1px or 0px as needed */ 
+  min-height: unset !important; /* v92.0 - for padding below 4px */
+}
+:root {
+  --arrowpanel-menuitem-padding: 6px 8px !important;
+}
+
+/*** Proton Tabs Tweaks ***/
+
+/* Adjust tab corner shape, optionally remove space below tabs */
+
+#tabbrowser-tabs {
+    --user-tab-rounding: 6px;
+}
+
+.tab-background {
+    border-radius: var(--user-tab-rounding) var(--user-tab-rounding) 0px 0px !important; /* Connected */
+    margin-block: 3px 0 !important; /* Connected */
+}
+#scrollbutton-up, #scrollbutton-down { /* 6/10/2021 */
+    border-top-width: 1px !important;
+    border-bottom-width: 0 !important;
+}
+
+/* 1/16/2022 Tone down the Fx96 tab border with add-on themes in certain fallback situations */
+.tab-background:is([selected], [multiselected]):-moz-lwtheme {
+    --lwt-tabs-border-color: rgba(0, 0, 0, 0.5) !important;
+    border-bottom-color: transparent !important;
+}
+[brighttext="true"] .tab-background:is([selected], [multiselected]):-moz-lwtheme {
+    --lwt-tabs-border-color: rgba(255, 255, 255, 0.5) !important;
+    border-bottom-color: transparent !important;
+}
+
+/* Container color bar visibility */
+.tabbrowser-tab[usercontextid] > .tab-stack > .tab-background > .tab-context-line {
+    margin: 0px max(calc(var(--user-tab-rounding) - 3px), 0px) !important;
+    height: 3px;
+}
+
+/* Override Normal Density height to Compact Density height (plus room for context-line) only for tabs 1/16/2022 */
+
+#TabsToolbar, #tabbrowser-tabs {
+    --tab-min-height: 37px !important;
+}
+    /* Tweak for covering a line at the bottom of the active tab on some themes 8/11/2021 */
+#main-window[sizemode="normal"] #toolbar-menubar[autohide="true"] + #TabsToolbar, 
+#main-window[sizemode="normal"] #toolbar-menubar[autohide="true"] + #TabsToolbar #tabbrowser-tabs {
+    --tab-min-height: 36px !important;
+}
+#scrollbutton-up,
+#scrollbutton-down {
+    border-top-width: 0 !important;
+    border-bottom-width: 0 !important;
+}
+
+    /* [Connected Tabs] Set a max height based on min-height plus margin-block: 1px 0 */
+#TabsToolbar, #TabsToolbar > hbox, #TabsToolbar-customization-target, #tabbrowser-arrowscrollbox  {
+    max-height: calc(var(--tab-min-height) + 1px) !important;
+}
+    /* [Connected Tabs] Make sure tab attention dot isn't too low - 10 Dec 2022 */
+.tabbrowser-tab:is([image], [pinned]) > .tab-stack > .tab-content[attention]:not([selected="true"]),
+.tabbrowser-tab > .tab-stack > .tab-content[pinned][titlechanged]:not([selected="true"]),
+#firefox-view-button[attention], .webextension-browser-action[attention="true"] {
+  background-position-y: bottom 8px !important;
+}
+
+#TabsToolbar {
+    --user-mute-button-height: 20px;  /* default size is 12px, site icon is 16px */
+}
+
+/* enlarge the move/mute button */
+.tab-icon-overlay:not([pinned], [sharing], [crashed]):is([soundplaying], [muted]) {
+    width: var(--user-mute-button-height) !important;
+    height: var(--user-mute-button-height) !important;
+}
+
+/*** Improve toolbar ***/
+#personal-toolbar-empty-description, toolbarbutton.bookmark-item:not(.subviewbutton) {
+    margin: 1px 2px !important;
+    padding: 3px;
+}
+
+#identity-box[pageproxystate="valid"].notSecureText > .identity-box-button, #identity-box[pageproxystate="valid"].chromeUI > .identity-box-button, #identity-box[pageproxystate="valid"].extensionPage > .identity-box-button, #urlbar-label-box {
+    margin-left: 2px;
+}
+