Describe the bug

The 'write' & 'preview' tabs are formatted weird with a narrow panel in the TA grading rubric panel:

'preview' doesn't even look like a tab that's clickable, it looks like floating text - a bug even.

Expected behavior

The github version of this editor looks a little more organized:

Even when the screen width is reduced, write & preview do not move. The formatting bar sacrifices a few icons as needed.