URL: https://google.com
Browser / Version: Firefox Mobile Nightly 55.0a1 (2017-06-06)
Operating System: Samsung Galaxy S6 (Android 7.0) - Resolution 1440 x 2560 pixels (~577 ppi pixel density)
Problem type: Something else - I'll add details below

Steps to Reproduce

1. Navigate to: https://goo.gl/reiexf
2. Observe image.

Expected Behavior:
Image has no background.

Actual Behavior:
Image has a gray background.

Note:

1. Reproducible on Firefox 53.0.2 Release and Nightly 55.0a1 (2017-06-06)) - Chrome UA.
2. Not reproducible on Desktop (Firefox, Chrome) and Chrome (Mobile) 58.0.3029.83.
3. Screenshot attached.

Watchers:
@softvision-sergiulogigan
@softvision-oana-arbuzov

sv; country: us

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