For some reason recently, I found STT stopped working on my updated Firefox v.55.0.3 (32-bit) and I desperately searched for a replacement add-on; all came up short.

Anyway, it seems the dev was working on this new Mozilla-mandated compatible one, and I was glad to have it back.

I don't mind donating for good apps (exts) I use frequently. I may install many, try *some* out, find them wanting, and subsequently remove them. This is not one of those; it's a definite keeper!
Besides being able to scroll all the way to the top and bottom, you all also have incremental scrolling up and down. There are also lots of customization options too.

Good on you dev for making a new version to work with Mozilla's new WebExtensions.