I've now seen this on two different databases in the past month.
A user edits a record in a form view and changes the value of a simple char field.
On saving, the field reverts to the 'old' value. The database stores the 'new' value. An export of the record produces a CSV with the 'new' value. Still, the UI shows the 'old' value. Restarting and refreshing the browser don't change this.
If I delete the record and import the CSV that was just exported, then the UI and the database are back in sync.
Has anyone else seen this and knows what is going on?
I've checked that there is no default value for the field, and no on_change event in the view definition, or any views that inherit.
What build are you running?