New $HOME breaks X programs
 

How to reproduce the problem
I found the solution here: If I start the GUI with startx instead of xdm I can start gui programs with new home (export HOME=/tmp/new-home).

So, probably the right question is: How can I configure XDM to start programs with new $HOME?

first set the new home and start xdm
but using $HOME is not the same as moving your home. Also modifying HOME is not a good idea.

Thank you, but I don't like this solution. I prefer to ignore / disable xdm and start X with startx.

I issue new home only for one program (firefox) because I test several versions. For example version-49 has java.

So, I don't want firefox to mess my profile files of my latest firefox (ESR) installation. I also test the latest installation (non-ESR), so I have three different homes for firefox.

I just don't understand. What do you want to achieve at all?

I want to protect my firefox profile from different version of firefox, ok I can mv temporary my main firefox profile before start the older / newer firefox, but if I forgot...

For example I use
to start wine without messing my main wine configuration

you might want to check firefox profiles: https://askubuntu.com/questions/2395...tory-from-bash

[SOLVED] New $HOME breaks X programs
 

Today I had the same problem. The above question is wrong. I remembered the XAUTHORITY file. The solution is to specify XAUTHORITY before new home.

In my case this seems fine.
Example working script here

You can have multiple profiles for every or any single user. This enables multiple versions all installed and running at once, just like Firefox developers do, by using the -no-remote startup switch, or exporting MOZ_NO_REMOTE=1.