Firefox crashes
Fiirefox started crashing after Avast free virus software was added together with its browser cleanup. Firefox comes up literally for a second, then closes. There is no crash report.
Opaite Mbohovái (1)
Hi, you can turn off Browser Cleanup, by opening Avast > Settings > Tools. You could also try turning off Grime Fighter and Software Updater.
Also, HTTPS Scanning has been know to cause problems, you can turn this off by going to Settings > Active Protection > Webshield > Customize.
If you have the tray icon enabled - Settings > General > Show Avast tray icon, you can right click on it > Avast shields control, and temporarily disable all shields.
Don't forget that you are reducing your protection by doing this, so if it doesn't work, you should perhaps turn them back on.
Hope something there will work.