many changes related to #1192:

- use CSS contain wherever possible to reduce subtrees of forced reflows
- reduced dependency between note and note_contents updates which will reduce number of updates to components
- optimization of "many rows" querying

src/public/app/widgets/title_bar_buttons.js

@@ -35,6 +35,7 @@ export default class TitleBarButtonsWidget extends BasicWidget {
         }
 
         this.$widget = $(TPL);
+        this.contentSized();
 
         const $minimizeBtn = this.$widget.find(".minimize-btn");
         const $maximizeBtn = this.$widget.find(".maximize-btn");