Was not able to reproduce on Windows.
I checked the Linux log (Project, UE4) and did not notice anything meaningful there. I used GDB to get a backtrace from the core dump file. Attaching that and an image of the callstack of my terminal when the crash was happening.
Viewport controls submenu opens
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-41634 in the post.