Brave 1.16.68 on Mac is reporting that WebGL GLSL highp precision isn't supported

[measuredweighed]

Description

As of 1.16.68 Brave on a desktop Mac reports that high precision WebGL shader variables aren't supported. This has not been the case before this update. Chrome Version 86.0.4240.111 (Official Build) (x86_64) works without issue, along with Safari and Firefox. All report support for highp WebGL shader variables.

Steps to Reproduce

The following Javascript will return false, where previously the correct result was returned.

const highp = gl.getShaderPrecisionFormat(gl.FRAGMENT_SHADER, gl.HIGH_FLOAT);
const highpSupported = highp.precision != 0;
if(!highpSupported) return false;

The call to getShaderPrecisionFormat returns:

WebGLShaderPrecisionFormat {rangeMin: 0, rangeMax: 0, precision: 0}

A visit to https://webglreport.com/ in Brave reports under Fragment Shader that float/int precision = mediump/lowp whereas the latest Chrome correctly reports highp/highp. Interestingly, it looks like for a WebGL2 context Brave behaves correctly.

I'm a complete novice when it comes to the Brave codebase but a recent commit by @pilgrim-brave may possibly be related? Apologies if this is totally unrelated.

Actual result:

Brave reports that high precision WebGL shader variables aren't supported.

Expected result:

Previously Brave has reported support correctly.

Reproduces how often:

Easily reproduced.

Brave version (brave://version info)

Version 1.16.68 Chromium: 86.0.4240.111 (Official Build) (x86_64)

[devcrowley]

I have confirmed that this issue also affects Brave 1.16.68 on Windows 10 Version 10.0.18362.720

[ben-mm]

FYI, I believe this is currently breaking the Autodesk Fusion 3D Viewer:

[kjozwiak]

Verification PASSED on macOS 10.15.7 x64 using the following build:

Brave | 1.17.69 Chromium: 87.0.4280.60 (Official Build) (x86_64)
-- | --
Revision | 12697cfeb273d7de95cf9b18350d2c457f58224c-refs/branch-heads/4280@{#1352}
OS | macOS Version 10.15.7 (Build 19H2)

Visited https://webglreport.com and ensured that float/int precision: appears as highp/highp as per the following:

Verification PASSED on Win 10 x64 using the following build:

Brave | 1.17.69 Chromium: 87.0.4280.60 (Official Build) (64-bit)
-- | --
Revision | 12697cfeb273d7de95cf9b18350d2c457f58224c-refs/branch-heads/4280@{#1352}
OS | Windows 10 OS Version 2009 (Build 19042.630)

Visited https://webglreport.com and ensured that float/int precision: appears as highp/highp as per the following:

---

Verification passed on

Brave	1.17.69 Chromium: 87.0.4280.60 (Official Build) (64-bit)
Revision	12697cfeb273d7de95cf9b18350d2c457f58224c-refs/branch-heads/4280@{#1352}
OS	Windows 7 Service Pack 1 (Build 7601.24544)

Visited https://webglreport.com and ensured that float/int precision: appears as highp/highp as per the following:

[Omiod]

Still not working ...