I created the launcher for the Ranger filemanager like this:
#!/usr/bin/env xdg-open
[Desktop Entry]
Version=1.0
Type=Application
Terminal=true
Icon[pl_PL]=/
Name[pl_PL]=Ranger
Exec=/usr/bin/ranger
Name=Ranger
Icon=/home/yemu/.icons/Ranger.png
Unfortunately, the icon only shows on the .desktop file, but after I run it, in the launches there's default grey icon with gear instead of the ine defined in the file.
I'm self posting the answer I found on the internet, here's my desktop entry, temporarily using baobab icon, but I hope I'll manage to change that. ranger shows up as an indepentent app, and I can swith to it with Super+Number, and that's mainly the thing I wanted to achieve. Using this method I also managed to add some bookmarks to the left-click menu of this launcher.
The crucial thing is to add wmclass and then set terminal as false.