videos not playing Thread

hello,

i am running firefox 80.0.1 (64bit) and for last few months i am having trouble playing any new video on the browser on moddb.

for example i can play this:

Moddb.com

but i can't play this:

Moddb.com

is this a codec issue?

i installed k-lite codec pack 15.5.6 but it's still same issue.