There was a possible problem early on. Perhaps I should have quit when, after the three mount commands near the beginning, "chroot . /bin/bash" brought this negative remark:
but "cat /etc/issue" brought the desiredbash: warning: setlocale: LC_ALL: cannot change locale (en-GB.UTF-S)
so I supposed that everything was all right. There were a lot of lines about "Cannot do [something or other to] locale" during the "apt-get install ubuntu-mate-desktop" but the next thing that really caused me to worry was when I followed the instructionUbuntu Wily Werewolf (development branch) \n \l
I suddenly noticed these two lines:Please leave the ubuntu MATE 15.10 chroot with
It looks like I was already out of chroot, and I "exited" into it!root@bart-desktop:/# exit
Also I had started the session with "sudo su" but when I typed
that was apparently no longer in effect: "only root can do that."mount --bind /tmp/.X11-unix ./tmp/.X11-unix
So I sudo su'ed again and the mount command worked, as did "xhost + local:," but this time "chroot . /bin/bash" got "chroot: failed ... No such file or directory"!
I went ahead with "export DISPLAY=:0" and "firefox" anyway, expecting nothing, but in fact a feeble version of Firefox did appear on screen. No menus or anything so I couldn't see what version it was trying to be. I can still get that firefox by cd-ing to /chroot-wily in a terminal and typing "firefox," but that's pointless.
Anyway, I guess my question is, should I have given up the first time the "/bin/bash" thing complained? And why wasn't I still in chroot when I wanted to exit it? Did some of the stuff I was downloading go to the wrong places?