Steps to reproduce:

https://developer.mozilla.org/en-US/docs/Web/HTML/Element/iframe

Print. Print to paper or print to PDF is same.

Actual results:

iFrame appears in Print Preview but actual printing causes iFrames to disappear. Can be replicated without wasting paper by printing to PDF.

Expected results:

iFrame should be printing, as it does in Chrome and Safari and Edge.

The Bugbug bot thinks this bug should belong to the 'Core::Printing: Output' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Issue reproduced (for the HTML Demo: <iframe> ) with the following steps:

1. Launch Firefox
2. Go to https://developer.mozilla.org/en-US/docs/Web/HTML/Element/iframe
3. Ctrl/Cmd + P
4. Print
   on MacOS 12 and Win 11 with Fx versions: 112.0.2, 113.0b8, 114.0a1 (2023-04-26)

It does not reproduce in Fx 102.10.0esr.

Regression
mozregression provided the following info:

• pushlog_url: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=17df1e9794687c0d56a85bc975e6b650c911b69f&tochange=9ce1bc0acf1544186bb85b062417d2a0a65efdb3
• Potentially regressed by: Bug 774398

Additional notes:

• the (HTML Demo: <iframe>) frame alone can be printed with the following steps: R-click on the frame ->This Frame ->Print Frame ->Print
• the map frame has never been printed correctly (checked in Fx 88)

:emilio, since you are the author of the regressor, bug 774398, could you take a look?

For more information, please visit BugBot documentation.

Set release status flags based on info from the regressing bug 774398

Moderately sure this should be fixed by bug 1800897.

Please reopen if you can repro after bug 1800897.

This seems fixed Nightly build 20230822040001, but I could still reproduce it on Firefox Beta 117, which i think is tracked in bug 1849569.