If you want to use software that must remain open all the time but you don’t want to have its icon in your Dock or in the switcher (Cmd + Tab), it’s possible, though it doesn’t always work in all cases.
There aren’t many prerequisites since the only thing you’ll need to be careful about is that before doing the following steps, your application must be closed.
Now, let’s get to the serious business. Go to your Applications folder and find the application you want to modify. In my case, I’m using XRG (a tool that creates graphs).
Right-click on the application, then “Show Package Contents”. Go to the “Contents” folder and edit the Info.plist file. There are only 2 lines to add at the end before </dict>:
You need to move the added lines elsewhere in the code; something is not working correctly. In the worst case, you can always delete the 2 added lines and the application will work as before.