Steps to reproduce the problem:
1. Create an ImageData object (constructor or createImageData() doesn't matter)
2. Fill with srgb data
3. Call putImageData()

What is the expected behavior?
Correct SRGB colors.

What went wrong?
Colors are much darker than expected. An unwanted SRGB to linear conversion is performed at some stage. This can be verified by doing the opposite conversion before feeding data to Chrome.

Did this work before? Yes Unsure, most likely 55

Chrome version: 57.0.2987.132  Channel: stable
OS Version: 7.1.2
Flash Version: 

Bug only happens when the canvas is large, so there seems to be multiple code paths.

Likely suspect:

https://chromium.googlesource.com/chromium/src/+/96126d211

This makes noVNC almost unusable on Chrome, so I would very much appreciate a high priority on this. Or a possible workaround. It doesn't help specifying color space to getContext() or createImageData().
 

Deleted: canvas.html 499 bytes

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