Copying an image from Firefox to Shapeshifter is broken

[mbrodesser]

When copying certain images from Firefox, preview in Shapeshifter is broken.

Steps to reproduce the behavior & expected behavior: Please see https://bugzilla.mozilla.org/show_bug.cgi?id=1742644#c1.

Desktop:

• OS: Windows.
• Browser: Firefox.
• Version ?

Presumably, this is not a bug in Firefox, see also the information linked at https://bugzilla.mozilla.org/show_bug.cgi?id=1742644#c5.

Feedback in the corresponding Bugzilla ticket, https://bugzilla.mozilla.org/show_bug.cgi?id=1742644, would be appreciated.