E.g. on this forum, when you login with Discourse, it opens a popup window that shows the vertical tab bar by default. Depending on the sidebar width in other windows, this can take up a lot of space and break the window content:
Possible ways out:
- Treat popup windows differently and hide the tab bar
- Auto-hide the tab bar when only 1 tab is open (might be rather weird for the sidebar layout where "Bookmarks" and "Reading List" are also part of the list)