My understanding of the dompdf and dejavu licensing is reflected in the copyright file:https://salsa.debian.org/nagios-team/icinga-php-thirdparty/-/blob/debian/0.12.1+ds-1/debian/copyright?ref_type=tags#L65-L81
Thank you for this link, indeed !
What makes you think that the Bitstream license is incompatible with the DFSG?
Sorry about that, It was a mistake in the diagnosis on my side. You helped me understand I was wrong on how I understood this license. -- William