These are the problems I have to report:
On the first issue, I'm not sure if it's an extension problem or an Opera problem. One of the threads crashes when memory is low. Only certain sites seem to be affected, and not all tabs. New windows always resolve the issue.
It seems that WhatsApp Beta in the sidebar causes it to malfunction. Logging in sometimes stops working, forcing the user to establish a new connection.My assumption is that the sidebar is sending some half-baked transactions.
The thread priority of the sidebar is probably too low for me, but this is an older AMD Fusion laptop.