I am running Linux Mint 18.3 XFCE and have installed snapd on it. I have the stable version of Chromium installed via snap and would also like to try out the beta version. However, when I attempt to install the beta version snap, I get a message back that I already have Chromium installed. Is it possible to have the stable and beta versions installed at the same time, or do I have to remove one to use the other?
You have to remove one to use the other by running sudo snap refresh --channel=beta chromium (refresh is the snap term for "upgrade"). Snaps can only co-exist when the snap_name is different.
UPDATE: Parallel Installs are now a thing, however, it is still in experimental status(as of 2021/6/14) and may not work well for many snaps.