Thanks @Erik Beuschau I have run some tests and do get it working sometimes in Firefox, but cannot see what I am doing wrong with the specific case.
I have a login flow that calls an api, on success it sets the session cookie and 'saves to session storage' a key / value for the user role.
based on the user role it then either redirects, or it makes another api call to retrieve some results and save some of that data to session storage, it is this 'save to session storage' that is not working (only in Firefox).
so within the same flow the first save to session storage works correctly across all browsers, but the second one remains undefined only in Firefox, and works in chrome and safari.
i have tried adding the "save to session storage' in numerous places throughout the workflow and with different key names and storing different data, but it always works in chrome and not in firefox .... seems really weird, but must be something to do with my end ...
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