Arma3 gets launched upon starting the launcher if steam is open.

[k-e-l-p]

Not much else to it apart from the title. Is this intended behaviour? If that's the case, I think that this should be toggleable. Will provide debug info upon request

[muttleyxd]

Are you passing any arguments to the binary? Please run arma3-unix-launcher --verbose and post logs here please.

 $ arma3-unix-launcher --help
Usage: arma3-unix-launcher [options] 

Optional arguments:
-h --help                      	show this help message and exit
-d --disable-steam-integration 	disable Steamworks SDK integration
-l --list-presets              	list available mod presets
-p --preset-to-run             	preset to run, launcher will start Arma with given mods and exit
--server-ip                    	server ip to connect to, usable only with --preset-to-run
--server-port                  	server port to connect to, usable only with --preset-to-run
--server-password              	server password to connect to, usable only with --preset-to-run
-v --verbose                   	verbose mode which enables more logging

If you pass -p parameter, then A3UL will try to start the game with given preset