We're going to check this again. I'll update soon.
Please record a video of this issue. Make the URL visible to allow us to check it.
i might have found something interesting,
when a new user has been added to the user base nothing happens, i can edit his account whitout the error.
only old users has this problem with the "invalid user id".
btw can the video be shared private? as there is some privacy info on those pages and i dont want get it to show to whole world, if you know what i mean.
I think this problem comes from your database. Your users are not created properly and some data is not created in wpForo User profile page. That users are "migrated users" or created with not standard registration ways. So I recommend synchronize user data using [Synch User Profiles] button in Dashboard > Forums > Dashboard admin page. If the problem is not fixed please take a screenshot of your WordPress/wpForo Database > wp_wpforo_profiles table structure and leave it here.