Allow vertical scrollbars to be disabled (user preferences, visible by default)

client/components/sidebar/sidebar.jade

@@ -1,5 +1,5 @@
 template(name="sidebar")
-  .board-sidebar.sidebar(class="{{#if isOpen}}is-open{{/if}}")
+  .board-sidebar.sidebar(class="{{#if isOpen}}is-open{{/if}} {{#unless isVerticalScrollbars}}no-scrollbars{{/unless}}")
     //a.sidebar-tongue.js-toggle-sidebar(
     //  class="{{#if isTongueHidden}}is-hidden{{/if}}",
     //  title="{{showTongueTitle}}")
@@ -33,6 +33,11 @@ template(name='homeSidebar')
       span {{_ 'hide-minicard-label-text'}}
       b  
       .materialCheckBox(class="{{#if hiddenMinicardLabelText}}is-checked{{/if}}")
+  ul
+    a.flex.js-vertical-scrollbars-toggle(title="{{_ 'enable-vertical-scrollbars'}}")
+      span {{_ 'enable-vertical-scrollbars'}}
+      b  
+      .materialCheckBox(class="{{#if isVerticalScrollbars}}is-checked{{/if}}")
   hr
   unless currentUser.isNoComments
     h3.activity-title

client/components/sidebar/sidebar.js

@@ -110,6 +110,11 @@ BlazeComponent.extendComponent({
     return user && user.isKeyboardShortcuts();
   },
 
+  isVerticalScrollbars() {
+    const user = ReactiveCache.getCurrentUser();
+    return user && user.isVerticalScrollbars();
+  },
+
   events() {
     return [
       {
@@ -134,6 +139,9 @@ BlazeComponent.extendComponent({
         'click .js-keyboard-shortcuts-toggle'() {
           ReactiveCache.getCurrentUser().toggleKeyboardShortcuts();
         },
+        'click .js-vertical-scrollbars-toggle'() {
+          ReactiveCache.getCurrentUser().toggleVerticalScrollbars();
+        },
         'click .js-close-sidebar'() {
           Sidebar.toggle()
         },
@@ -155,6 +163,10 @@ BlazeComponent.extendComponent({
       return false;
     }
   },
+  isVerticalScrollbars() {
+    const user = ReactiveCache.getCurrentUser();
+    return user && user.isVerticalScrollbars();
+  },
   showActivities() {
     let ret = Utils.getCurrentBoard().showActivities ?? false;
     return ret;