Allow column width configuration: allow stretching navbar with columns

src/components/desktop_nav/desktop_nav.scss

@@ -23,6 +23,26 @@
     max-width: 980px;
   }
 
+  &.-column-stretch .inner-nav {
+    --miniColumn: 25rem;
+    --maxiColumn: 45rem;
+    --columnGap: 1em;
+    max-width: calc(
+      var(--sidebarColumnWidth, var(--miniColumn)) +
+      var(--contentColumnWidth, var(--maxiColumn)) +
+      var(--columnGap)
+    );
+  }
+
+  &.-column-stretch.-wide .inner-nav {
+    max-width: calc(
+      var(--sidebarColumnWidth, var(--miniColumn)) +
+      var(--contentColumnWidth, var(--maxiColumn)) +
+      var(--notifsColumnWidth, var(--miniColumn)) +
+      var(--columnGap)
+    );
+  }
+
   &.-logoLeft .inner-nav {
     grid-template-columns: auto 2fr 2fr;
     grid-template-areas: "logo sitename actions";

src/components/settings_modal/tabs/general_tab.vue

@@ -122,6 +122,11 @@
             {{ $t('settings.right_sidebar') }}
           </BooleanSetting>
         </li>
+        <li>
+          <BooleanSetting path="navbarColumnStretch">
+            {{ $t('settings.navbar_column_stretch') }}
+          </BooleanSetting>
+        </li>
         <li>
           <ChoiceSetting
             v-if="user"