It happens on many sites but not all. A recent example is on https://www.sega.com, the images on that page, in the section "Whats happening", do not show when trying to print using ctrl+p from Firefox browser. I have tried varied settings changes for "print headers & footers" & "print backgrounds" & other settings both on & off but those images do show show in the print.

For me, the YouTube items in WHAT'S HAPPENING load and can be printed, and the Twitter and Facebook items do not load and so of course they do not print. It could be because of tracker blocking in my case.

In your printout, are the images missing (replaced with Alt text), or is the section is cut off, etc.?

In Firefox all images load on the page and the page looks as I would expect but when selecting ctrl+p for print, it leaves out the images from within the "whats happening" section. I have also turned off enhanced protections for Firefox and Ublock Origin entirely for this website but the images still do not show in that section for printing.

I have experienced similar issues on other websites where images are also not showing. I have attached a jpg of the page created from the pdf screen print for further info.

Yes, now that I look more closely, the YouTube ones do not show up in print preview for me, either. The page has a print media style rule that makes the thumbnails transparent. I don't know why. Comparison screenshots, showing the Page Inspector panel with regular style rules and print media style rules, attached. (To open the Inspector panel right-click/Ctrl+click the thumbnail while in regular view; it's not possible during print preview.)

Yes I can see the error showing in the inspector panel but even with all Firefox extensions & my own router exclusions turned off, the error is still there.

Here is the error that shows for me "Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://syndication.twitter.com/settings?session_id=febc9d3671ecfca6f6686d5895643ffabafd988f. (Reason: CORS request did not succeed). Status code: (null)."

A further explanation from that error is shown on this page... https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS/Errors/CORSDidNotSucceed.

The same error also shows in Brave & Safari browsers for this webpage https://www.sega.com. I have not previously inspected other pages with print image issues, could this be a webwide software issue or change that is causing this? Is there anything else I or Firefox can do to fix this issue?

Yes I can see the error showing in the inspector panel but even with all Firefox extensions & my own router exclusions turned off, the error is still there.

It's not an error, it's what the page says should happen: hide images when printing.

Here is the error that shows for me "Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://syndication.twitter.com/settings?session_id=febc9d3671ecfca6f6686d5895643ffabafd988f. (Reason: CORS request did not succeed). Status code: (null)."

I don't know what that settings file is, but the problem is caused by a Sega rule, not a Twitter rule.

Is there anything else I or Firefox can do to fix this issue?

I don't think Firefox is going to intentionally ignore styling instructions just to fix one site, unless it's a hugely important site. In this case, since you know the style rule that causes the problem, you could manually disable it by opening the Inspector, switching to the print emulation mode, hovering over that rule, and unchecking it. I can't remember whether I tested that, but you might give it a try. Obviously if you need to print multiple pages per day, that's a pain and maybe there is a better solution but off the top of my head, I'm not sure how to fix it.

Thank you for your help, I will research this further if needed.