About 4-5 versions ago Firefox developed a problem where runaway scrolling can occur on Facebook. I stopped reading those threads, so I don't know the status of fixing it. In case it helps, here's a link to run a search for facebook scroll threads during the past 6 months:

https://support.mozilla.org/en-US/search/?w=2&all_products=1&q=facebook scroll range:question_updated:gte:now-6M/M

This is the active bug report: https://bugzilla.mozilla.org/show_bug.cgi?id=1779404

How about a link directly to the resolution????

It hasn't been resolved.

It's not a META issue.... It's a browser domain issue... The code writers at Chrome have it handled... But I like Firefox... Wish Firefox would hire Chrome code writers....

I think the issue occurs when the "viewport" -- the visible part of the page -- is shorter than a certain height. That is affected by screen resolution and zoom level. You could try zooming out (hold down Ctrl and tap the - key once to reduce zoom to 90%) and see whether that helps. Of course, if the text becomes too small to read, that doesn't really help...