Created attachment 1963 [details] Backtrace I have a defined action: python -c 'print 80*"-"+"\n"'; > (ie, insert 80 dashes followed by a newline) This has worked for years without problem. Recently, it often but not always locks up claws. Today I have a backtrace, attached, reporting a corrupted double-linked list. Current version I'm running is 3.17.3git156, although it started happening before that version. Keith