GNOME Command to increase / decrease screen brightness

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I recently bought a chromebook that is now running Fedora. To get the brightness keys working, I installed xbacklight, and have set shortcuts to commands that run xbacklight -inc 3 and xbacklight -dec 3, and it gets the job done.*

This, I realize, actually has a couple drawbacks. First, the little GNOME overlay showing screen brightness doesn't pop up the way volume does. Second, running xbacklight seems to take more processing power than whatever the default command is. If I run the command multiple times quickly, whatever else I'm doing tends to lag.

So I'm looking for a way to implement the default behavior. An ideal answer would be:

• A native GNOME command that replaces xbacklight -inc 3 or whatever.
• A command that calls the usual ALT + F7 or ALT + F8 keystrokes without remapping the function keys.