My gnome workflow was:
* I have many windows open
* I press a key (super) to get the misson-control like overview.
I type in "Firefox"
* It will run the app if it's not already running, or switch to it.
If there's something that can emulate that, and... Not be a hacky work around.. then I'm all ears
That’s how it works on macOS. Command-space (or whatever way you want to trigger Spotlight) then type Firefox and it will bring it to the front, or launch it if it’s not running. No workarounds or third-party software needed.
