The bug
Sprinting via double-tapping the "forward" button cannot be bound separately from the "forward" button itself. This means there is no way (outside of hunger) to not sprint when tapping the "forward" button in quick succession, which may be required for precise positioning.
This may be considered a feature request but for a control to be absent from configuration does not seem right.
How to reproduce
Double-tap your usual forward button while grounded and the hunger bar is full if applicable
Note that this causes sprinting
Change the forward keybind to an unused key such as G
Double-tap this new key and note that you still start sprinting, demonstrating that it follows the "forward" key
Expected behaviour
The double-tap-to-sprint behaviour would not follow the forward movement button.
Actual behaviour
This functionality is hardcoded to always be stuck with the move forward button. There exists no option to disable it, nor is it a different rebindable control that happens to share the move forward key's place by default.
How to fix
There are several ways in which this issue could be fixed:
Preferable solution: There would be two different keybinds for sprint: one which defaults to LCONTROL, and a second that defaults to W. W is also the default forward key, so pressing W once would trigger normal walking whereas pressing it twice would activate sprinting and cause the player to move forward. If the sprint key and forward key do not share a keybind, the "new" sprint keybind would work identically to the normal sprint keybind. The "Random Patches" mod for 1.16.5 uses this behaviour.
The "Controls" menu could contain a toggle which would determine whether pressing the forward key twice should activate sprinting, or not.
Linked issues
is duplicated by 2
relates to 4
Attachments
Comments 10
Also true for double-tapping space for flying. If you would like to include it here you may but it's up to you.
@unknown Flying has been reported under MC-256811.
Double tapping whatever button you use for "forward" will always activate sprint when double-tapped. I don't believe this can be changed without modding the game. The button which activates sprint (without double tapping forward) can be changed in your key bind setting though.