-e: see title, tested in FF Beta (46) and nightly (48), canary(51)

-repro:
--create empty 3D project
--save default scene and add to build target
--add WebGL 2.0 at the top of the graphics APIs
--build and run for WebGL
--NOTICE error spam in browser console

Error: WebGL: texImage2D: Invalid internalformat/format/type: 0x1908/0x1908/0x8d61 ca33435d-14dd-4dbd-927e-6dd5d9d333c4:1:325042
glGetIntegerv: GL_INVALID_ENUM: enum argument out of range

(Filename: D:/Mercurial/unity/Runtime/GfxDevice/opengles/ApiDebugGLES.cpp Line: 512)

ca33435d-14dd-4dbd-927e-6dd5d9d333c4:1:190791

OpenGL Error after calling glGetIntegerv()

(Filename: D:/Mercurial/unity/Runtime/GfxDevice/opengles/ApiDebugGLES.cpp Line: 512)