Basic code completion in IntelliJ on Mac

I think that the question is motley asking to what key combination do you change it, and why JetBrains haven’t implemented the update to the mac keymap by themselves.

Anyways, I’ve swapped the Ctrl+Space with Alt+Space which doesn’t seem to collide with any MacOSX system key shortcut.

You either disable/change Spotlight shortcut in the system settings or you change the Basic completion shortcut in IDEA Preferences | Keymap.

Alternatively, you can use Ctrl + Shift + Space for "SmartType" to avoid collision with Spotlight.