How can I neutralize this annoying "use the app" popup on Reddit while using Firefox Android mobile?

By not using reddit?

I mean, Reddit isn't the only website with these shitty popups. Surely there a general way to kill them other than disabling JavaScript entirely?
- Of course they can be disabled. But sites are not all built the same way, so there isn't one silver bullet we can tell you about to disable them everywhere. On mobile it's even more difficult because access to browser plugins is more limited, along with developer features within the browser.
  
  I also use FF on Android, and until recently was also using Reddit. There isn't a good way to remove that bar.
lol

If you're running uBlock Origin, go into the addon settings, go to Filter Lists, and turn on the Annoyances filters. They're not on by default, but should get rid of these kinds of "known" popups across popular sites.

Specifically, it's the Easylist - Notifications filter that seems to do it for Reddit.
- "AdGuard – Mobile App Banners" does the trick too.
Awesome, never knew this!
Thank you!

Use Lemmy 😂

You can try requesting the desktop page or use old.reddit.com

I did try to install this add-on https://addons.mozilla.org/en-CA/firefox/addon/old-reddit-redirect/ but the installation button is grayed out :(
- On Firefox Beta/Nightly you can enable Debugging Menu, by going to About on settings, and tapping the logo 3 times.
  
  There you can add Custom Add-on collection.
  
  You can create developer account on Mozilla, and add any add-on that you want.
- Firefox on Android only allows a select few add-ons unless you install a nightly version or something. I don't do it myself but it should be easy to Google

I think old.reddit.com bypasses it.

Not responsive of course, but servicable

For now. There was a reddit post last week that showed reddit was trialing blocking all mobile traffic that doesn't come from the app. Using "desktop" mode in most browsers won't save you either as the user agent still leaks that it's a mobile browser.
- I'm not saying that corporate reddit has a history of acting intelligently, but requiring mobile traffic to use the app might be the dumbest thing they could do.
  
  That's actually going to lose them traffic.

You can click continue, at least until Reddit blocks Mobile browsers entirely, use a third party app, at least until Reddit kills them off, or stop using Reddit.

Given the behaviour of apps, I think I will use only websites from now on.

Does Firefox have a fine grained way to kill these scripts, or is disabling JavaScript for all websites the only option ?
- You can disable JS per site with an add-on. For example, uBlock origin works on mobile Firefox on Android, and you can use it disable JavaScript on any domain you want without impacting others.
They lock mobile browsers entirely for NSFW subs unless you are logged in.
- Fuck Reddit

If you just want to read you also could use libreddit.

Libreddit instances

There is the Tampermonkey addon for Firefox Android which lets you install user scripts. I found this user script which is supposed to do what you want but it doesn't seem to work for me. Maybe it needs to be updated.

But I think in general you're better off using a third-party app as suggested in the other comments. I would recommend RedReader since it's open source and has been given unrestricted API access by Reddit due to its accessability features (at least for now, who knows what Reddit decides to do next).

There are ublock origin rules that manages to block it, i think it’s available by looking on Google for a reddit post about it. Of course you need to install ublock origin extension before.

You can also use a mirror. Teddit and LIbreddit are great.

Thanks, although I suspect they will die with the API chances :(