Firefox environment variable - DESKTOP_STARTUP_ID


I noticed that the firefox process launches with the following environment variable set:


where myhostname is the string at /etc/hostname
and the string of digits at the end changes only when I restart firefox.
This variable does not show up on the about:support page.

Could you please help me understand the meaning of this environment variable and how it is set at startup ?

How did you find that out?

I am using a CLI utility called htop, but I assume it only parses the string at /proc/PID/environ

That is the first thing I used trying to find out how you got that.

top as well

I don’t see that with either of those tools.
doesn’t exist (on my system)

Sorry, I should have provided more details.
In htop, I highlight the firefox process (not the childIDs), and push the E key on my keyboard.
By PID I meant the string of digits corresponding to the firefox process, it should appear in the first column of htop.

Ah, I see now.
Thank you!

I was curious - since I could not find it in the actual environment variables that you get with
But I cannot help you with your initial question. Sorry!

searching the interweb leads to:

Communicating from a launcher process to a launchee process

To communicate the startup sequence information from a launcher
process to a launchee process, when possible an environment variable
should be used:

value of the “ID” field in the “new” message

Thanks for sharing the url @freggel.doe
Do you know how is the value for this environment variable generated when launching firefox from Whisker Menu?

Just found out that xfce’s whisker menu includes an option in the launcher of each app, called Use startup notification. Un-ticking that option unsets DESKTOP_STARTUP_IP when launching apps from the menu. Interesting feature that I didn’t know it exists.