Bug in master (related to docbook changes?)

[Pavel Sanda]

On Thu, Jul 09, 2020 at 10:26:21AM +0200, Jürgen Spitzmüller wrote:
> * Open a new document and type something.
> * Open document settings
> * Change something (e.g., font)
> * Apply
> 
> Now Update and View are disabled unless you close and reopen.

bisect actually points to 3c094c739ba38f4 ...
Author: Richard Kimberly Heck <rikiheck at lyx.org>
Date:   Wed Jul 8 23:59:15 2020 -0400

    Simplify code a bit. Should be equivalent, unless backs is empty!
P