Is using a 3rd-party software updater program to update Microsoft Edge WebView2 on Windows safe, or maybe it is best to only use a 3rd-party software updater program as a reference, which I already do?
And leave that task to be automatically performed by Microsoft Edge Chromium and Windows. However, the only downside to that course of action is that it usually takes a few days for it to be updated.
I mostly manually update Microsoft Edge Chromium from within its Help and Feedback > About window. It is a convenience trade-off between maybe risking to brick one's system or not being fully updated.
Good luck!