I've tried the following in Opera Stable, Opera Next, and Opera Developer on my MacBook Pro running Catalina:
If I drag the ssl icon that is next to a site's url in the address bar down to the bookmark bar...opera crashes.
Something must have changed between v64 & v65, because it only happens on builds 65.0.3467.38 and above. Downgrading to Opera 64.0.3417.92, the crashing no longer occurs.