Avast showed me nothing. The Opera icon simply wasn’t there under Browser Integration or Browser Cleanup.

Once I’d uninstalled Opera and reinstalled but changing it to the default All Users option the Opera icon appeared underneath that for my default browser: Firefox which itself is underneath the IE icon as in your screenshot of the Browser Integration screen. So I now have all three browsers shown.

The WebRep icon now appears in the Opera toolbar and I’ve since found that it is possible to shift it to the right so it’s now set-up to display very much like I’ve become used to with Firefox.

I’m just really evaluating Opera, not sure whether I’ll keep using it, but working as it should do with Avast was important. There are Opera some features I prefer over Firefox but others, like the bookmark system isn’t quite as good.