The AJAX/FCK problem is known about - I had a similar issue here. Perhaps in 4.8 the Control was set to SupportsPartialRendering by default? (so new installs would have the problem but old ones would not?)

I've unchecked "Supports Parial Rendering" in the user account control, but edits made to the biography are still not saved.. if the profile is edited by going through the Manage Profile link on the user's profile.

However, when the biography is edited as part of a new user registration the edits are saved.

Then if I edit the bio via Manage Profile, the new edits are not saved, but the existing edits remain. 

 

Kmideas wrote I solved my issue by updating 'supportparitalrendering'  from 1 to 0 in the 'Edit User Accounts' field w/in ModuleControls. User Account was already 0, I assume because I unchecked it in the control.

Can you explain the details of what you did as it is not working for me?

Thanks