Command line instructions to uncheck “Select the previous input source” on macOS

Still on the subject of post macOS clean reinstall tips, if control + space stops doing what it is supposed to do — such as autocompletion suggestions on Visual Studio Code —, it is probably caused by macOS global shortcut.

Check if Settings > Keyboard > Keyboard Shortcuts… > Input Sources and see if “Select the previous input source” and “Select next source in input menu” are checked. If so run:

defaults write com.apple.symbolichotkeys.plist AppleSymbolicHotKeys -dict-add 60 "<dict><key>enabled</key><false/></dict>" defaults write com.apple.symbolichotkeys.plist AppleSymbolicHotKeys -dict-add 61 "<dict><key>enabled</key><false/></dict>" 

This will do the same as unchecking boxes, and will require a reboot to be accounted for, but it probably belongs to your own reinstall script.