lyx 2.4.0 -alpha3 error in make install

[Wolfgang Engelmann]

lyx 2.4.0 -alpha3 error in
sudo make install
using Debian

...
+checking for package biblatex [biblatex]... yes
+Inspection done.
+Read the file doc/LaTeXConfig.lyx for more information.
LyX: Fertig!
LyXRC.cpp (260): Conversion failed for /home/wolfgang/.lyx/preferences
Warning: Die Konfigurationsdatei konnte nicht gelesen werden
----------------------------------------
Fehler beim Lesen der Konfigurationsdatei
preferences.

Bitte prüfen Sie Ihre Installation.
(Please check your installation)

What should I do?


I had before lyx 2.4.0dev
and did not remove it before doing the new
./configure
make
sudo make install

Wolfgang