Bugzilla

Thanks - that's really handy to know.

It sounds like there's some about:config preference that's enabled-by-default only in Nightly (and perhaps has been for a little while).  That would explain why you're seeing it working in current Firefox Nightly and also in older builds launched from mozregression (which uses archived Nightly builds).

In the interests of getting to a state where a Mozilla developer can take a look at an affected page -- I'm wondering the issue might reproduce in a saved copy (in which case you might be able to share that and we could investigate without needing to literally be a seller).

Could you try the following:
1. Load up a page with a shipping label that's ready to print in one of the affected sites, like right before you would normally get to a broken print preview dialog.
2. Do `File|Save As` (or `Hamburger-Menu | Save Page As`)
3. Make sure the save dialog shows "Web Page, Complete" as the save-type.
4. Try loading the saved file and see if it reproduces the issue.
5. If so: make a zip file that has the saved html file and its accompanying resources folder (e.g. `foo.html` and `foo_files/`) and send that to dholbert at mozilla dot com, and I can take a look?

Thanks - that's really handy to know.

It sounds like this is related to some about:config preference that's enabled-by-default only in Nightly (and perhaps has been for a little while).  That would explain why you're seeing it working in current Firefox Nightly and also in older builds launched from mozregression (which uses archived Nightly builds).

In the interests of getting to a state where a Mozilla developer can take a look at an affected page -- I'm wondering the issue might reproduce in a saved copy (in which case you might be able to share that and we could investigate without needing to literally be a seller).

Could you try the following:
1. Load up a page with a shipping label that's ready to print in one of the affected sites, like right before you would normally get to a broken print preview dialog.
2. Do `File|Save As` (or `Hamburger-Menu | Save Page As`)
3. Make sure the save dialog shows "Web Page, Complete" as the save-type.
4. Try loading the saved file and see if it reproduces the issue.
5. If so: make a zip file that has the saved html file and its accompanying resources folder (e.g. `foo.html` and `foo_files/`) and send that to dholbert at mozilla dot com, and I can take a look?