Some people would install Opera, run it once (from the installer, which runs Opera when it's finished) and never run it again, perhaps because they didn't know that the red 'O' that appeared on their dock is actually a browser.

Not to turn this into a discussion, but it seems a bit implausible to me that a big number of people actually downloaded Opera, knowing it's a browser, started it, and then couldn't find it because the name didn't contain the words internet browser.

Would be interesting to know how these tests were made.

Or is this based on diagnostics that tells you that lots of users only started Opera once and not again?

It's not a mistake. We changed the name so that people would find Opera easier.

My initial feeling is it looks rather silly, though I guess it doesn't really matter.

Just curious as to why you decided on this change. Did you do usability testing and noticed that people couldn't find Opera and start it on their computers?

Some of my speed dial thumbnails (previews?) are missing. I deleted the thumbnails.db file to have Opera re-create the database and re-generate the thumbnails, and although some are now showing, others that were there before are now missing instead. Right clicking and reloading doesn't do anything. I'm running Opera 23.0.1522.75. Is this a known issue?

And most importantly, the Next and Previous Tab menu items are missing in the Window menu and can therefore not be remapped (System Preferences Keyboard > Shortcuts).

Yes, along with other commands like Clone Tab, Reload, Copy Address. It would be nice if all commands were available through the menus.

All commands should be accessible through the main menus so that keyboard shortcuts can be assigned and changed using the System Preferences. Clone tab and Copy address are among commands missing and only available via right click.

Fair enough, but that's only valid for the hover effect. Opera's buttons don't change even in their pressed state, which buttons do in e.g. Finder or Safari.

Furthermore I think the reason I find the lack of hover effect jarring in Opera is that its buttons don't really look like buttons in other OS X apps, those are usually outlined and look like well... buttons.

In Opera 18 there is no hover/mouse over effect on the toolbar buttons. When I move the cursor over a button or click one there is no visual feedback. Is this really by design?