Custom launchers have come so far from when stock Android and smartphone user interfaces and skins weren’t that nice to look at.
Android Q wants to end them and here’s why Google doesn’t want you installing launchers like Nova.
This is how Google wants to do that
When a custom launcher is installed, the default gesture navigation is made unavailable on Android Q as Google has greyed out that part. 
This recent discovery was made by Charizarlslie on Reddit. He explains that switching to launchers like Nova on Android Q, navigations automatically switch from gesture to the three button navigation.
You also get this notification.
So now you’re left with gesture navigation from the custom launcher and since they’re not system level, they will be unstable and shaky.
Presumably, Google is trying to rein in on the inconsistency across Android regarding gesture navigation.
