I have the same issue with Logitech MX Vertical - mouse4 and mouse5 buttons are working perfectly as back and forward buttons throughout macOS including all web browsers except Opera. This bug only started happening recently. I'm still hoping Opera team will fix this annoyance as the bug is obviously introduced locally to the Opera browser.
@leocg ... (take two) all these ads are driving me crazy. But being able to log into places that I couldn't do yesterday, is a good sign.
Once I've tried everything, I'll let you know. There is lots to test and a full plate on top of that, so please be patient with me... but I'll be back.
I want to apologize for the unclear nomenclatures – it is a plugin that passes the url (or text snippets if you like) to the external application DevonTHINK. Even if DevonTHINK is running, there is no content »arriving«, because opera just lack the necessary permission.
The bug was already reported by others some time ago, but my hope was to get help now, since opera and the plugin have left some versions behind.
It worked! I didn't restore the entire profile folder just the three bookmark files, favicons and history files and my bookmarks bar is exactly like it was before. Happily back to 58 and mouse works and no more freezes.
I think I jumped on the gun too quickly. It's not Opera. It's their own damn app not working in any browser. This has been resolved now. This thread can be disregarded.