Strange. Usually when enabling debuglevel 9, the log is way bigger. Try pasting more of the log. You have only posted the few lines which indicate firefly is closing.
Precisely, I only pasted the lines indicating the crash.
The entire log (of multiple sessions) is about 130 MB. : )
However, everything above those lines was in regards to the scanning. Then those lines popped “out of nowhere” and Firefly crashed.