How do i find out what was my previous forefox version, and then where can i downoad it for reinstallation

This latest version doesn't work properly, (unable to download videos), and i want to return to the earlier version but i don't remember what it was. How do i find out my previouse version? Only the supported mac versions are listed on the older versions download site. How can i access all firefox versions through 131,0? Thank you for the help, you are most kind. mac os sonoma 14. firefox ver 131.0; Hank H