If you would like to use my Heise Single Page extension to enhance readablilty of the news site. Now there is a workaround for Android after mozilla decided to stop allowing any addons on the android version of firefox:

1. Install Firefox nightly: https://play.google.com/store/apps/details?id=org.mozilla.fenix
2. Enable Debug Menu in Firefox nightly:
   1. Open Settings
   2. Scroll down to the end, click "About"
   3. Tap the logo at least 10 times until you see a toast message announcing "Debug menu enables"
   4. Go back one level
3. In the extended section select Custom Add-on collection:
4. Enter these details:
   1. User ID: 14027677
   2. Collection name: AllMyAddons
   3. 
5. Go back and select the add-on from the proposed list
   1. 

The collection features more than my own addon now, because the collection is not stacking on top of the default one.

Why do I have to do that?

Well the truth is, since mozilla dropped general add-ons with firefox 79 in August this is the first and currently only way to use not so popular extensions on android.