The bottom line starting with Translate active page is not visible in the Opera, so no possibility to translate the web page ...

Not the same in my case. I am using an external monitor, but it is constantly connected to my MacBook Pro, I do not change or connect/disconnect. Nevertheless the Opera gets unresponsive.

Update:
When I open the Opera, it works without any issue for couple of hours. And then suddenly the workspace switching come very slow and the CPU goes up to 100%.
When I closed and reopen the Opera, it works flawlessly again for couple of hours.

The switching workspaces on Macbook Pro is very slow, it takes even half a minute. I have 3 workspaces with avarage 6 tabs in each.
My version is 73.0.3856.344
Can you help on this please?
Thank you in advance.