There's another issue I'd like to bring to your awareness. I'm not sure, if this is a consistent bug but lately I've realized a problem with notifications.
Using WhatsApp in the sidebar e.g. brings me the message: Activate your notifications every other day. And there's also an issue with Google Drive which even says that it can't activate notifications.
I'm on this actual and most recent version Opera One but made a reinstall. I turned on "Block Third Party Cookies" and activated every preinstalled adblock list in Opera. So this might be interfering, but I haven't had this before. So maybe this also is an issue connected with one of the last updates.

@Opera-QA-Team Thank you very much!

I eventually even got an update for my MacBook to version 122...150 Stable, which might really be a Mac specific one.
But both updates haven't solved the inconsistencies in the themes feature, unfortunately.
https://forums.opera.com/topic/86544/theme-not-consistent

It only happens with "Classic Theme" by the way, when you are trying to change the color.
If you choose one theme from the gallery, everything's fine.

I modified my theme from blue to green but as you'll see in the following screenshot: The color above the address bar hasn't changed to green, but it's still blue.
While configuring in the editor it was green as intended, but after saving it changed to blue again. This seems to be a bug, as it hasn't happened before.