Showing different blocks/sections for different browsers.

After having some embedded videos blocked by people viewing the my site in Firefox, I learned that non encrypted videos are blocked on that browser (And other similar browsers such as Brave/Opera etc), whilst working fine in Chrome and Safari.

I'd like to use some custom css to display slightly different versions of the block/section for different browsers. (Similar to hiding/showing different versions of sections/blocks on mobile vs desktop).

Has anyone successfully done that?

Many thanks