Here's how to reproduce (most of the time):
- Have the library open in a tab.
- Have the rest of the workspace filled with other resources so there is no empty space.
- Right click on the main library icon and choose "Open in a new tab"
Result: You don't get a new tab, but the existing library goes blank. To get it back, just "Open in a new tab" again, or close and re-open.
I've tested this on beta 10 and beta 11.
