Steps to reproduce:
- Open https://gerrit.wikimedia.org/r/c/mediawiki/core/+/378251/7/resources/lib/easy-deflate/deflate.js
- Change the view from "Side By Side" to "Unified"
- Maximize the browser window
Expected behaviour: The content occupies the whole screen width (or at least enough width to show the longest line)
Actual behaviour: The content occupies the same width as one half of the "Side By Side" view