feat: move extensions from prefs menu's left pane to General->Advanced section (#718)

app/assets/stylesheets/_sn.scss

@@ -100,6 +100,24 @@
   }
 }
 
+.sn-accordion-arrow-icon {
+  &[data-is-expanded='true'] {
+    transform: rotate(180deg);
+  }
+}
+.accordion-contents-container {
+  transition: all 0.23s ease-out;
+  transform-origin: top;
+  transform: scaleY(0);
+  height: 0;
+
+  &[data-is-expanded='true'] {
+    height: auto;
+    transform-origin: top;
+    transform: none;
+  }
+}
+
 /** Lesser specificity will give priority to reach's styles */
 [data-reach-custom-checkbox-container].sn-switch {
   @extend .duration-150;
@@ -273,6 +291,9 @@
 .mb-5 {
   margin-bottom: 1.25rem;
 }
+.mb-8 {
+  margin-bottom: 2rem;
+}
 
 .max-w-89 {
   max-width: 22.25rem;
@@ -525,6 +546,10 @@
   left: -14rem;
 }
 
+.right-0 {
+  right: 0;
+}
+
 .-right-2 {
   right: -0.5rem;
 }

app/assets/stylesheets/_ui.scss

@@ -126,6 +126,9 @@ $screen-md-max:              ($screen-lg-min - 1) !default;
 .mt-5 {
   margin-top: 1.015625rem;
 }
+.mt-8 {
+  margin-top: 2rem;
+}
 
 .p-0 {
   padding: 0rem;