The phrase is "...as you indicate with your use of Firefox"! It is NOT "...as you indicate with your Firefox user preferences." Using Firefox is what indicates your agreement, similar to how using your credit card indicates your agreement with the card terms. I take it back - the meaning is not ambiguous at all.
I'm at a loss as to how to proceed from here, given that we seem to have different ideas of how the English language works.
However there's more that also precludes such use as in your example:
> license to use that information to help you navigate, experience, and interact
Mozilla phoning home your bank account details is not helping you do that in any way, so it is not covered. The next part, that we seem to disagree on, only further narrows that down to actual user intent.
You're not indicating that they can have a license to do anything, you're specifically giving them a "license [..] to help you [..] as you indicate".
