Sourcetree for Mac (4.1.3) on macOS Big Sur (11.6) often crashes the entire system causing the screen to go black and then to reboot entirely. As far as I can tell this has occurred for me on macOS Big Sur for at least a few versions of Sourcetree and persists in version 4.1.3. It seems to happen when the app is refreshing the diff for file status changes or maybe checking the remote for unpulled commits. I've tried switching repositories from HTTPS to SSH but it still occurs. I also thought maybe it could be related to the "Window restoration" preference for which I'm using the "Restore windows on startup" option to have Sourcetree reload repository windows as tabs when the apps starts. Because of this unpredictable issue, I've had to stop using Sourcetree entirely for now, thought it is by far my preferred Git client. I look forward to getting back to using it if this issue can be resolved.