Mobile usability improvements

[amrmelsayed]

A few usability improvements for Android and iOS based on the latest testing cycle:

• The feedback buttons were too small without enough hit slop.
• The detailed feedback section wasn't rendering properly.
• The scroll to bottom button wasn't auto-hiding when the user scrolls towards the bottom of the page.
• Updating thread loading indictor to detect whether the user is in the process of transitioning from one thread to another thread.