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I have reproduced the issue you are having. Hidden fields are indeed shown when you try to edit your submissions. As far as I have checked this issue has already been forwarded to the developer team to be fixed. I will let the related team know about your issue too. This may accelerate the process as the number of users that have had this problem increases.
You can check this thread to see if there are any updates about this bug. I have already added your thread as a heads up. So, developers will let you know in any case when the problem is resolved.
Thank you for reporting this.