Created attachment 377699 [details] Description, Screenshots and Recreation Steps for the Bug. See the attached pdf. tl;dr: Cross domain cookies are set properly, but if I visit enough websites and collect enough cookies, I am no longer able to access my original 3rd party cookies. This leads our users to get redirected from a 3rd party site to a first party one, where the cookies are visible, so they are considered logged in. This symptom of the problem leads to an infinite loop between the 3rd party and first party sites.
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