Several people encountered random freezes with a Qt environment (KDE or LxQt) and Intel chipset on Fedora 23. Here's the report:
https://bugzilla.redhat.com/show_bug.cgi?id=1317145
Did anybody hit this with F24? If yes, I think we should propose it as blocker, because it sounds like a nasty issue.
--- Giulio juliuxpigface (jpigface on IRC)