FWIW, this is intentional by design, at least when the original stubb attribution feature was implemented. We don't block downloading Firefox whilst waiting on a stub attribution auth request. That request has to happen before the user clicks download on a button that points to /thanks/.
Bug 1689106 Comment 1 Edit History
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FWIW, this is intentional by design, at least when the original stub attribution feature was implemented. We don't block downloading Firefox whilst waiting on a stub attribution auth request. That request has to happen before the user clicks download on a button that points to /thanks/.