why is it where I am viewing a pdf in firefox and then send it to printer, it prints all left justified

I am on Firefox 152.0 (64-bit). When I view a pdf in Firefox it looks centered like a normal page. When I send it to print from there, it left justify the pages. I have tried changing the Scale, Margins. The paper size is Letter 8.5" x 11". I have 2 different Canon printers (laserjet and inkjet) and no difference. If I download it and open it with Microsoft Edge and send it to print, it prints centered like a normal page. I have tried to search articles on this topic. They were all very old. Some says to make changes in about:config in the address line. I tried a couple. Yet no difference. Hope you can help. Si-Yih