Moving your thunderbird data to a custom location

Thunderbird's profile data is stored in ~/.thunderbird by default.
If that's inconvenient, i.e. due to disk quota limits, here's is how to move the profile folder. It will have some random name, we'll call it pr0f1le.default, and ~/.thunderbird contains a file profiles.ini and a folder named pr0f1le.default.
Here, I've moved the profile folder to e.g. /media/data/thunderbird/pr0f1le.default and changed profiles.ini to (changes in bold):

[General]
StartWithLastProfile=1

[Profile0]
Name=default
IsRelative=0
Path=/media/data/thunderbird/pr0f1le.default
Default=1

IsRelative has to be 0 because I've given Thunderbird an absolute path to the new location.