Yes, but it supports the custom addon collection feature. This way you can use it in a browser that isn't based on the beta/nightly branches, and should be less crashy. I run Fennec to access a few privacy redirect extensions, largely to make reddit and twitter less awful to browse without their respective apps.

I had been using Fennec for a while and had no idea! Instructions here: https://old.reddit.com/r/fossdroid/comments/p7mgec/guide_usi... (also, collection names should not contain spaces, it seems)

Requires AMO registration