I did
run synaptic package manager
search for firefox
clicked on firefox, then in the menu bar, did package->force version, then let it install 136.0.1+linuxmint1+virginia
on my system, then went back into addons and re-enabled ublock, which was the only thing I was running
if you're paranoid, you can backup bookmarks and stuff before you do the upgrade
I've been trying for weeks to upgrade FF manually by downloading and installing. This is a step in the right direction. I just have to find a way to enable the extension. Thanks again.