Firefox getting too slow or bloaty for you?
I've been checking out the latest build of Vivaldi browser the last couple days. Nice and responsive; it works with Google extensions so you can get an adblocker or whatever from there. I only use ublock origin from there. It's not in the repositories (maybe experimental?) but Vivaldi provides a 32 and 64-bit deb package. (https://vivaldi.com/download/). If you search for "vivaldi testing branch" you can find an installer script for non Debian/Redhat systems. They make it hard to find for some reason.
If some multimedia isn't working, launch Vivaldi from a terminal; it will display a curl command you can use to get a multimedia file from an Ubuntu repository.