This seems to happen randomly - but often - on intention invocation
mostly (AltEnter), but also on search usages (AltF7).
I can only force kill the app and restart it. At first restart no class
validation would be enabled, no reindexing takes place. Then after a
normal quit/start again, it would reindex an reenable all validation.
I've had this dozens of time today, it's really really annoying as you