feat: Always show the remaining overflowed button if only one is left, b=no-bug, c=common

src/browser/components/customizableui/CustomizableUI-sys-mjs.patch

@@ -1,5 +1,5 @@
 diff --git a/browser/components/customizableui/CustomizableUI.sys.mjs b/browser/components/customizableui/CustomizableUI.sys.mjs
-index d9a059f608779fea7cd8c595a432f6fe95183e0c..a3c18551e3b24ee86a4373cbbc4f2cdb074aa94d 100644
+index d9a059f608779fea7cd8c595a432f6fe95183e0c..7f6493ced4abb1f6ba54242b8ee213a74f01aea5 100644
 --- a/browser/components/customizableui/CustomizableUI.sys.mjs
 +++ b/browser/components/customizableui/CustomizableUI.sys.mjs
 @@ -14,6 +14,7 @@ ChromeUtils.defineESModuleGetters(lazy, {
@@ -127,15 +127,7 @@ index d9a059f608779fea7cd8c595a432f6fe95183e0c..a3c18551e3b24ee86a4373cbbc4f2cdb
      this.notifyDOMChange(aNode, aNextNode, aContainer, false, () => {
        this.setLocationAttributes(aNode, aAreaId);
        aContainer.insertBefore(aNode, aNextNode);
-@@ -3306,7 +3305,6 @@ var CustomizableUIInternal = {
-     if (!this.isWidgetRemovable(aWidgetId)) {
-       return;
-     }
--
-     let placements = gPlacements.get(oldPlacement.area);
-     let position = placements.indexOf(aWidgetId);
-     if (position != -1) {
-@@ -4541,7 +4539,7 @@ var CustomizableUIInternal = {
+@@ -4541,7 +4540,7 @@ var CustomizableUIInternal = {
     * For all registered areas, builds those areas to reflect the current
     * placement state of all widgets.
     */
@@ -144,7 +136,7 @@ index d9a059f608779fea7cd8c595a432f6fe95183e0c..a3c18551e3b24ee86a4373cbbc4f2cdb
      for (let [areaId, areaNodes] of gBuildAreas) {
        let placements = gPlacements.get(areaId);
        let isFirstChangedToolbar = true;
-@@ -4552,7 +4550,7 @@ var CustomizableUIInternal = {
+@@ -4552,7 +4551,7 @@ var CustomizableUIInternal = {
          if (area.get("type") == CustomizableUI.TYPE_TOOLBAR) {
            let defaultCollapsed = area.get("defaultCollapsed");
            let win = areaNode.ownerGlobal;
@@ -153,7 +145,7 @@ index d9a059f608779fea7cd8c595a432f6fe95183e0c..a3c18551e3b24ee86a4373cbbc4f2cdb
              win.setToolbarVisibility(
                areaNode,
                typeof defaultCollapsed == "string"
-@@ -5843,6 +5841,7 @@ export var CustomizableUI = {
+@@ -5843,6 +5842,7 @@ export var CustomizableUI = {
    unregisterArea(aName, aDestroyPlacements) {
      CustomizableUIInternal.unregisterArea(aName, aDestroyPlacements);
    },
@@ -161,7 +153,7 @@ index d9a059f608779fea7cd8c595a432f6fe95183e0c..a3c18551e3b24ee86a4373cbbc4f2cdb
    /**
     * Add a widget to an area.
     * If the area to which you try to add is not known to CustomizableUI,
-@@ -7890,11 +7889,11 @@ class OverflowableToolbar {
+@@ -7890,11 +7890,11 @@ class OverflowableToolbar {
          parseFloat(style.paddingLeft) -
          parseFloat(style.paddingRight) -
          toolbarChildrenWidth;
@@ -175,7 +167,7 @@ index d9a059f608779fea7cd8c595a432f6fe95183e0c..a3c18551e3b24ee86a4373cbbc4f2cdb
      });
  
      lazy.log.debug(
-@@ -7909,7 +7908,8 @@ class OverflowableToolbar {
+@@ -7909,7 +7909,8 @@ class OverflowableToolbar {
        Math.max(targetWidth, targetChildrenWidth)
      );
      totalAvailWidth = Math.ceil(totalAvailWidth);
@@ -185,7 +177,17 @@ index d9a059f608779fea7cd8c595a432f6fe95183e0c..a3c18551e3b24ee86a4373cbbc4f2cdb
      return { isOverflowing, targetContentWidth, totalAvailWidth };
    }
  
-@@ -8003,7 +8003,7 @@ class OverflowableToolbar {
+@@ -7970,7 +7971,8 @@ class OverflowableToolbar {
+             return;
+           }
+         }
+-        if (totalAvailWidth <= minSize) {
++        let isLastItem = win.gZenVerticalTabsManager._hasSetSingleToolbar && this.#target.id == 'zen-sidebar-top-buttons-customization-target' && this.#overflowedInfo.size == 1;
++        if (totalAvailWidth <= minSize && !isLastItem) {
+           lazy.log.debug(
+             `Need ${minSize} but width is ${totalAvailWidth} so bailing`
+           );
+@@ -8003,7 +8005,7 @@ class OverflowableToolbar {
          }
        }
        if (!inserted) {
@@ -194,7 +196,7 @@ index d9a059f608779fea7cd8c595a432f6fe95183e0c..a3c18551e3b24ee86a4373cbbc4f2cdb
        }
        child.removeAttribute("cui-anchorid");
        child.removeAttribute("overflowedItem");
-@@ -8348,7 +8348,7 @@ class OverflowableToolbar {
+@@ -8348,7 +8350,7 @@ class OverflowableToolbar {
          break;
        }
        case "mousedown": {

src/zen/common/ZenCustomizableUI.sys.mjs

@@ -37,7 +37,7 @@ export var ZenCustomizableUI = new (class {
   }
 
   #addSidebarButtons(window) {
-    const kDefaultSidebarWidth = '210px';
+    const kDefaultSidebarWidth = '215px';
     const toolbox = window.gNavToolbox;
 
     // Set a splitter to navigator-toolbox

surfer.json

@@ -19,7 +19,7 @@
       "brandShortName": "Zen",
       "brandFullName": "Zen Browser",
       "release": {
-        "displayVersion": "1.16.3b",
+        "displayVersion": "1.17b",
         "github": {
           "repo": "zen-browser/desktop"
         },
@@ -39,7 +39,7 @@
       "brandShortName": "Twilight",
       "brandFullName": "Zen Twilight",
       "release": {
-        "displayVersion": "1.17t",
+        "displayVersion": "1.18t",
         "github": {
           "repo": "zen-browser/desktop"
         }