Libreoffice calc 6.1 update - Extensions are not working

Hi,
I’m using LibreOffice Calc on Linux (Debian stretch). After update to libreoffice_6.1.0~rc2-3_amd64.deb the extensions are not working anymore. See below the message when I try display extensions in the Extension Manager:

" com.sun.star.deployment.DeploymentException: Document is empty
Line: 1
Column: 1"

Any idea to solve the problem?
Regards,