How can I hide an app from the dock while keeping it in the menu bar?

There's a messaging app I often use that includes both a menu bar icon (to hide/show the window, as well as indicate how many unread messages there are) as well as the app itself which resides in the dock/launchpad. I want to know if there's a way to hide the app from my dock when the app is running so that I can simply use the menu bar to see if I have any new messages and thus save dock space. I know that this is possible as some of my other apps already do this (e.g. LastPass for Mac ), but is there a way to do this manually, e.g. through the Terminal? I am currently on MacOS Catalina Beta (although I assume the solution should also work for earlier versions too).