We also have the same issue, has anyone found a solution or even a cause for this? We noticed that the "autosubmit" only happens the first time the user visits the safari sign in page, if the user revisits the page, the auto submit is not occurring and the user can press the login button, which works (the user is redirected to the app as expected). After a few minutes, if the user visits the page again, the form goes back to autosubmit (initially), until the user visits the page again. Very strange.

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