I have been referred here from the support forum. Here is the thread - https://support.mozilla.org/en-US/questions/1292664 - the response from your expert indicates that this defect is known about but has not been addressed. This needs fixing.
My position as a user is that it is unacceptable that one of the major desktop browers is unable to Print or Save to pdf, whilst preserving all the fonts, images, and links. Worse, people are not being alerted that this functionality is deficient, and they may not be checking this for themselves but relying on FF’s good name and assuming that it is actually working. Please refer to the support thread for details. Thanks in advance for getting this sorted out. It is also necessary, whilst the fix is being worked on, to alert users who might otherwise be unaware that they have a saving issue with PDFs.
I created a roundup of 17 PDF creation extensions and it’s not a pretty picture: