I have attempted multiple fresh installations of Firefox Nightly, including previous versions. Upon start-up, Nightly opens the profile selection screen, and promptly hangs. Only response is the Windows error sound upon clicking anywhere within the profile selection window. I frequently have problems with Developer Edition and Nightly every time Windows forces a system update. To solve issues with Developer Edition, I usually have to roll back to version 79, then walk the versions forward. Similar techniques have worked with Nightly in the past, however current attempts are failing at the profile window. Since I am unable to get past profile creation, crash reports and dump files are not being generated.