A significant number of my current Firefox addons are not WebExtesions based addons and so don't work in Firefox 57 and later. Since I'm going to have to move on from Firefox 56 at some point (although probably not soon, temptation notwithstanding), I've been checking in on the state of WebExtensions addons and putting together a snapshot of the addons that I would likely end up using if and when I move over.

(Since Firefox WebExtensions addons are very new at this point and some addon maintainers are undoubtedly getting to experience the charms of unexpected and not entirely welcome popularity, I would be surprised if this list did not change over the next six months or so.)

The simple case is current addons that already have Quantum-okay versions. In this category are NoScript, uBlock Origin, Open in Browser, and HTTPS Everywhere. I'm not exactly fond of the new NoScript interface (I find it much more confusing than the old Firefox 56 NoScript UI), but I'm sure I could get used to it.

As far as everything else goes:

• Foxy Gestures appears to be the leading replacement for FireGestures. The FG Github site has a bunch of useful information, including about current inherent limitations in WebExtensions that affect Foxy Gestures. The leading other option is probably Gesturefy, which I haven't experimented with (and it seems less actively developed, which matters when the Firefox WebExtensions API is actively changing as people tell Mozilla what they left out).

• My preferred way to deal with cookies is the 'don't allow cookies at all' approach. Unfortunately, it seems that everyone has moved over to the 'accept cookies then delete them later' model (as far as I can see from picking through addons.mozilla.org). The modern addon for this that I'm trying out is Cookie AutoDelete, partly because it's developed in the open on Github.

  (For all that I grumble about this, accepting cookies and then throwing them away may make various websites somewhat more usable. On the other hand, I already read enough random things on the Internet as it is.)

• The replacement for It's All Text that I've experimented with so far is Textern; it has a somewhat convoluted install process but once installed it appears to be close to the It's All Text experience. Textern uses Native Messaging (also, and), which is pleasantly straightforward compared to some of the alternate approaches taken by other addons. The one thing I've had to remember is that its magic file needs to be installed into every strongly isolated Firefox instance.

  (The It's All Text Github repo mentions some other alternatives. Everything I've looked at so far appears to have a pretty heavyweight process for going from adding the extension to 'edit textarea in vim in an xterm', although they're probably better if you want deep integration into a highly advanced editor.)

• The alternatives to FlashStopper that I've been looking at are Disable Autoplay for YouTube and Disable HTML5 Autoplay but neither of them get stellar reviews; there's also this. Some flaws may be inevitable in the brave new world of WebExtensions, where apparently at least some addon operations have to wait for the page's DOM to be fully realized, whereas YouTube's player can start up before then. Or maybe there aren't any really good Firefox extensions here yet.

  Apparently setting the media.autoplay.enabled preference to false may also do this, but there are reports of side effects (and when I look at the Firefox source code, I can't convince myself that this disables all video autoplay in all situations). Or I could see if the WebExtension version of NoScript can handle this on its own now.

(In looking at things to make Youtube less annoying, I just stumbled over YouTube Stop AutoPlay Next. I hate that particular YouTube behavior so I may experiment with this at some point.)

It's quite possible that I've missed some good options for replacement addons here. In fact, given that some areas are a bit disappointing, I actively hope that I have (and that I can find the better choices someday). And of course I have no idea whether these new addons (or in some cases new WebExtensions versions) will handle memory any better than my current set of addons do. Since I have had terrible luck with changing addons in the past, I live in moderate fear that they'll be worse, which is one reason I am so unenthused about changing anything about my relatively precarious addon environment. It may leak a bit now, but it could be much worse (and has been in the past).