@Videonauth Thanks for posting a good answer to my last question. You may also be interested in answering this new question: Materials on linux shell error message pattern. The OP posted another question on a similar topic which was closed for being too broad and this question would benifit from some editing too.

some heavy editing, maybe you can tell me about an oddity i just encountered answering another question, im actually bashing my head in on that one

and trust me i tried togather with the OP many things in chat, you can find the room in the comments

@Videonauth Even though it's not what the OP asked about, someone might post another answer suggesting that instead of adding a custom quicklist-entry to a .desktop file the OP could create aliases for starting firefox from the terminal with different options.

well yes but i want this working now as much as the OP :)

and foremost i want to understand why it is behaving like it behaves

For example this answer has a special option for starting Google Chrome from the terminal in OS X: superuser.com/questions/986421/…

creating a new icon in .local/share/applications should show up in the list of icons

what we found out so far is that exporting the variable before starting strats firefox but as soon i create a custom .desktop file the original firefox is not showing anymore in the launcher, as well not the new one

under unity however all works as it should lol

i even made a VM with 17.04 just to test this

only gnome does not want to play ball

Don't delete the 17.04 VM guest OS when 17.04 goes EOL in January. You can still use it for trying weird things that maybe won't work.

oh i have a complete install ready here and i know how to get the old-releases updated wo the point they where when they went EOL

in fact you even can update an old 6.10 to the point where it was when it went EOL