Affected versions

• Firefox Nightly 70.0a1
• Firefox DevEdition 69.0b9
• Firefox 68.0.1esr

Affected platforms

• Windows 10
• macOS 10.14
• Ubuntu 18.04

Steps to reproduce

1. Start Firefox
2. Access https://en.wikipedia.org/wiki/Los_Angeles_County,_California
3. Click on any image found on the page
4. Click again to zoom the image
5. Click on back button to exit fullscreen then close the image with X in the upper right corner of the page
6. Access any other image and click again to zoom it.

Expected result

• The image will be opened in a new tab.

Actual result

• Clicking on the image to zoom it further, will close the image preview.

Regression range

• Not a recent regression, I will look for a regression asap.

Additional notes

• The issue is kind of intermittent, but if triggered once, will easily be reproducible after
• The steps and issue can be seen on this attachment.

Bugbug thinks this bug is a regression, but please revert this change in case of error.

Nothing related to APZ here. I'm tentatively moving this to ImageLib.

It seems that the issue has been fixed by other patches, as it is not reproducing anymore on latest Nightly 70.0a1 (2019-08-07).