@ghost

With Pointer Cancellation, there is

Completion of the function is on the up-event, and a mechanism is available to abort the function before completion or to undo the function after completion;

A point that is confusing me is the comma. Does this mean ...

Completion of the function is on the up-event, and a mechanism is available to abort the function before completion
OR
to undo the function after completion

Or does it mean ...

Completion of the function is on the up-event,
AND
mechanism is available to abort the function before completion
OR
to undo the function after completion

To take this to an extreme, what about a link that is automatically activated on mouse down? This would not be in scope for On Input (which notes "Clicking on links is activating the control, not changing the setting of that control.")

In this example, the user can just press some back button (e.g. the browser back button, or a back button on the form). Let's say it's not a submit button that irreversibly submits the form.

Would it fail because completion is on the down event, even though the user can undo it? Or would it pass because they can undo it after completion?

I would understand it better it is was...

Abort or Undo

Completion of the function is on the up-event and one of the following is true:

• a mechanism is available to abort the function before completion
• a mechanism is available to undo the function after completion

..or...

Abort

Completion of the function and a mechanism is available to abort the function before completion.

Undo

A mechanism is available to undo the function after completion