Media keys and default keybindings

Modify Mint 20.3/Chromebook to provide five keyboard layouts customized for Chromebooks.  Download the file xkb.tar.gz from this website. Then execute these lines from a terminal window:

Then reboot the computer

Media keys and Function keys can be accessed either with or without pressing the "Overlay" key first, depending on your choice of keyboard layout.  I recommend using the overlay media key method.  Select the "Chromebook Right alt overlay" configuration from the

OS menu: LM / Control Center / Keyboard Preferences / Layouts.

Keyboard Layouts

Layout Name Overlay Key Top row keys Top row keys with Overlay
Chromebook / No overlay / F keys mapped to media keys None Media keys Media keys
Chromebook / Right alt overlay Right-Alt Function keys Media keys
Chromebook / Right alt overlay / F keys mapped to media keys Right-Alt Media keys Function keys
Chromebook / Search overlay
previous default (1.0beta1), and Crouton default
Super (Search) Function keys Media keys
Chromebook / Search overlay / F keys mapped to media key Super (Search) Media keys Function keys

These layouts are stored in /usr/share/X11/xkb/symbols/chromebook* . To modify the functionality of a key, one can make changes to the appropriate file (as root).
For instance, in the file "chromebook_ralt" the power key is mapped as Delete, by the line

key <POWR> { [ Delete ] };

and setting the power button to "Do nothing" in the Power Manager dialog.

Key Mappings for highlighted selection

Key Combination
F1-F10 Accessed directly
F11 Overlay + ' (between ; and Enter)
F12 Overlay + \
Media Keys
Overlay + F1..F10
Home Overlay + Left Arrow
End Overlay + Right Arrow
Page Up Overlay + Up Arrow
Page Down Overlay + Down Arrow
Delete Power Button
Caps Lock Right-Alt as Overlay: Overlay + Right Shift

A computer reboot is required if any key bindings are changed.