Affected versions

• 81.0a1 (BuildId:20200804215246)

Affected platforms

• Windows 10 64bit
• macOS 10.14
• Ubuntu 18.04 64bit

Preconditions

• Ensure that the print.tab_modal.enabled pref is set to true

Steps to reproduce

1. Launch Firefox.
2. Open a new tab and access the following link
3. Click the print button.

Expected result

• The print preview is displayed.

Actual result

• The system dialog is displayed.

Regression Range

• I don’t think that this is a regression

Notes

• It seems that Chrome opens the print preview & I’m wondering if Firefox should act the same. I couldn’t find a bug that treats this but, if this is being tracked somewhere else, please free to duplicate this.

This is essentially a duplicate of bug 1602410, although that isn't at all obvious to non-devs I admit. I'll leave this open for now to avoid more duplicates being filed, but I'll take it off the list of bugs blocking bug 133787 to avoid inflating the already large list of frontend bugs and making it harder for the devs to see how much work is left. (Obviously please put it back on that list and flag it if for any reason things don't work once bug 1602410 is fixed.)

In theory this should be fixed now. Emil, would you mind re-testing it in tomorrow's nightly to see if that's the case?

I can confirm that this is fixed using Firefox 81.0a1 (BuildId:20200819212829) on Windows 10 64bit, macOS 10.14 and Ubuntu 20.04.

The print preview gets successfully open instead of the system dialog.

https://testrail.stage.mozaws.net/index.php?/cases/view/1081129