[Affected versions]: - Firefox 51 beta 13 - latest Developer Edition 52.0a2 - latest Nightly 53.0a1 [Affected platforms]: - macOS Sierra 10.12.2 [Steps to reproduce]: 1. Start Firefox 2. Visit http://webglsamples.org/WebGL2Samples/#draw_instanced_ubo [Expected result]: - Demo is displayed successfully [Actual result]: - Demo is not displayed. [Regression range]: - This issue is not a recent regression, it also reproduces on an old Nightly build (2016-07-12), where webgl2 was enabled by default. [Additional notes]: - Unable to display the demo in Chrome Canary as well. - Console output: > Error: WebGL: Disallowing antialiased backbuffers due to blacklisting. draw_instanced_ubo.html:70:18 - Graphics: Features Compositing OpenGL Asynchronous Pan/Zoom wheel input enabled; scrollbar drag enabled WebGL Renderer ATI Technologies Inc. -- AMD Radeon HD 6750M OpenGL Engine WebGL2 Renderer ATI Technologies Inc. -- AMD Radeon HD 6750M OpenGL Engine Hardware H264 Decoding No Audio Backend audiounit GPU #1 Active Yes Vendor ID 0x1002 Device ID 0x6741 Diagnostics AzureCanvasAccelerated 1 AzureCanvasBackend skia AzureContentBackend skia AzureFallbackCanvasBackend none TileHeight 512 TileWidth 512 - I did try on two other macs (iMac 21.5-inch, Late 2013 and MacBook Pro Retina 13-inch, Early 2015), both with Intel graphic cards (Intel Iris Pro 1536 MB and Intel Iris Graphics 6100 1536 MB) and the demo was shown just fine.

Yes, we blocklist MSAA on ATI+Mac since bug 695912 (2011).

Mass wontfix for bugs affecting firefox 52.