Hi @amoreno,
I tried your solution and now installing works fine (thank you!)
but now i get an error trying to produce a pdf Odoo:
Wkhtmltopdf failed (error code: -6). Message: b'The switch --header-spacing, is not support using unpatched qt, and will be ignored.The switch --header-html, is not support using unpatched qt, and will be ignored.The switch --footer-html, is not support using unpatched qt, and will be ignored.QXcbConnection: Could not connect to display \n'
im on Odoo 12.0-20190918 with Ubuntu 16.04.6 LTS
Kind regards
Anthony