Improving user experience of ABrowser add-ons manager

The release of Trisquel 8 will bring in a new wave of interest, and (hopefully) new users. In order to impress and retain these new users, it would help if the user experience of the flagship browser was as good or better than vanilla Firefox on Ubuntu.

On the ABrowser add-ons page, it says:

>> This is a list of libre extensions, themes and translations for the browser. It is a work in progress, we need volunteers to add content to the list. If you want to help, please ask in the forums/mailing lists. <<

I'd like to help. The problems I see using ABrowser 59.0.2 on Belenos are:

* installing add-ons doesn't work, as discussed here:
https://trisquel.info/en/forum/trouble-add-ons-abrowser

* even if it did work, the UX is jarring. When I search for an extension, then click on it's name to proceed with installation, the appearance of the page changes to the Trisquel.info CSS. This gives the (hopefully false) impression that my browser has been hijacked, and I may be about to install a fake malware version of my chosen add-on.

* there is no way to tell if any part of the installation process uses HTTPS to prevent MitM attacks injecting fake malware versions of add-ons. Does it?

* when I search for add-ons no license info is available, nor links to source code. Am I installing an add-on under a copyleft license, or a laissez faire one? Surely this is something we want to encourage even Jane Average users to take at least a passing interest in?

* Many of the add-ons found in searches are unmaintained or obsolete.

* There may be newer free code add-ons that are not yet available from the ABrowser add-ons system.

* For a search like "video download", there is a confusing array of choices, with very little information to guide my selection. Dealing with the previous two points may help, and I get that we want to be fair to all free code add-ons devs by including their add-ons without fear or favour. But the hard reality is that some of these add-ons are more user-friendly and more consistently effective than others. Could we create a system for reviews and ratings by the Trisquel community, so that the add-ons we experience as being better are more prominent in search results?

Some of these issues may be specific to Belenos, in which case they are less urgent to fix, as new users are most likely to install Flidas. But it would still be good to address them.