Hi
First of all, I love Firefox. I have 99% migrated from Chrome to Firefox. The only thing that keeps me with Chrome is PDF search, annotations and printing.
A big issue I found is when I open PDF in Firefox and want to modify it by saving only selected pages, let's assume PDF has 100 pages and I want to print (save as PDF) only pages from 90-100, it will save them almost correctly. The new PDF will have pages from 90 to 100, but, the massive issue is, the PDF doesn't have selectable text. While the original PDF is a proper PDF with graphics and text I can select and copy, the new generated PDF with selected pages does not contain selectable TEXT. I think the whole PDF is saved as png or just as graphics and all the text is removed? This is a massive thing that is important to me and makes me come back to Chrome once in a while.