the bloody mount points. I couldn't believe that when I realised what was going on. I got the wire brush and dettol out and scraped it off my drive. Never, ever again.

It won't work if $HOME is not under /home. Really. Not even if you softlink. You need a bind mount

Plus, have you seen how many loopback mounting points it creates? "df" becomes very hard to use as it buries your actual drives with it's own. One for the daemon, one for GTK, one for Gnome, one for each of the snaps you have installed....

By design, snap apps have no access to /etc. They live in their own little world, but instead of a normal chroot, they are splatted all over the standard Linux filesystem layout. With other bits mounted hither and thither. Its a mess, and subject to change with each release.

A bind mount is basically where you mount a given directory on top of an existing one. Suppose you have a RAID array where you have a partition mounted at /home2, containing some larger user accounts. If you wanted to remount /home2/user to /home/user (to sidestep issue #1), without the issues that come along with symlinks (it is not a directory, just a token that points to it), you'd do something like mount --bind /home2/bob /home/bob and the directory will then be traversable from both locations. The target folder must exist, same as any mount point. The end result is somewhat similar to a symlink, but instead of creating a special filesystem object, it utilizes the operating system's filesystem mounting machinery to do it, which makes it more transparent to running software. Tools like 'du' and 'find' will still be aware that they are cross filesystem boundaries, and will also behave as such if the bind mount is entirely within a given filesystem. Finally, as they're transient by nature (unlike symlinks), they need to be placed in fstab or some startup script to make them persistent.