Firefox wont return after execution

However i install firefox - via choco install firefox or followed by
./FirefoxSetup.exe -ms /MaintenanceService=false. Any execution thereafter like "C:\Program Files\Mozilla Firefox\firefox.exe" -CreateProfile "TestUser C:\Temp\ffprofiles\TestUser"(take for given that C:\Temp\ffprofiles\TestUser exists) runs, but never returns. See Also the browser test framework testcafe, which uses firefox in headless mode, never succeeds in opening the browser. See

P.S. Tested same commands on windows 10, those always execute as expected. Also, the travis ci build under linux - minus the above windows commands of course - succeeds. Also, chrome works as expected in the travis windows environment. Just can not get firefox to work.