2 xenial or not 2 xenial, that is the question

There is only 1 ubuntu release supported under Crouton, and this is xenial. All the older releases are end-of-life, and the newer ones are marked as not supported. Actually, xenial reached end-of-life on April 30 of this year. Nevertheless, it is still a powerful release, and works nearly perfectly with Crouton. About the only glitch is the thing which happens when a removable device is inserted while you're in the chroot: "Not allowed". However, the device can still be accessed after you clear the error by clicking OK.

Also, there are several PPA's which can be used to upgrade or add to the existing software. I'm familiar with these media-related packages: smplayer, guvcview, simplescreenrecorder, handbrake, and kodi. There may be others. I may return and provide links for these at a later time.

You can install bionic with a simple hack: look for a tutorial on here called "3 steps to install bionic beaver". Focal is easy to install, although cras doesn't get compiled until and unless you issue the update command in Crouton. You don't really need cras in focal, so just used alsamixer normally.

I'm interested in the future of Crouton. We shall see...