Here is a report that I generated with wktesthunter for the flakiness of this tests since 259359@main to 260782@main : The bot wpe-release completed 407 runs on the interval [259359@main-260782@main] Frecuency of results for test: fast/canvas/webgl/webgl2-texture-upload-enums.html 407 times [100%] -> TEXT -- The bot wpe-release completed 292 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance2/extensions/ext-color-buffer-float.html 160 times [54.8%] -> TEXT 132 times [45.2%] -> PASS -- The bot wpe-release completed 292 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance2/extensions/ext-color-buffer-half-float.html 160 times [54.8%] -> TEXT 132 times [45.2%] -> PASS -- The bot wpe-release completed 292 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance2/reading/read-pixels-from-fbo-test.html 292 times [100%] -> TEXT -- The bot wpe-release completed 292 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance2/renderbuffers/invalidate-framebuffer.html 182 times [62.3%] -> TEXT 110 times [37.7%] -> PASS -- The bot wpe-release completed 292 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance2/renderbuffers/multisample-with-full-sample-counts.html 182 times [62.3%] -> TEXT 110 times [37.7%] -> PASS -- The bot wpe-release completed 291 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance2/rendering/blitframebuffer-test.html 169 times [58.1%] -> TEXT 122 times [41.9%] -> PASS -- The bot wpe-release completed 286 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance2/rendering/fs-color-type-mismatch-color-buffer-type.html 286 times [100%] -> TEXT -- The bot wpe-release completed 286 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance2/rendering/rgb-format-support.html 164 times [57.3%] -> TEXT 122 times [42.7%] -> PASS -- The bot wpe-release completed 282 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance2/textures/image_bitmap_from_video/tex-2d-r8-red-unsigned_byte.html 180 times [63.8%] -> TEXT 102 times [36.2%] -> PASS -- The bot wpe-release completed 282 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance2/textures/video/tex-2d-r8-red-unsigned_byte.html 158 times [56.0%] -> TEXT 124 times [44.0%] -> PASS -- The bot wpe-release completed 293 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance/context/premultiplyalpha-test.html 293 times [100%] -> TEXT -- The bot wpe-release completed 293 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance/extensions/webgl-draw-buffers.html 293 times [100%] -> TEXT -- The bot wpe-release completed 293 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance/glsl/bugs/conditional-discard-in-loop.html 293 times [100%] -> TEXT -- The bot wpe-release completed 293 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance/limits/gl-min-textures.html 288 times [98.3%] -> PASS 5 times [1.7%] -> TEXT -- The bot wpe-release completed 293 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance/rendering/gl-scissor-test.html 149 times [50.9%] -> TEXT 144 times [49.1%] -> PASS -- The bot wpe-release completed 293 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance/textures/image_bitmap_from_video/tex-2d-rgb-rgb-unsigned_byte.html 164 times [56.0%] -> TEXT 129 times [44.0%] -> PASS -- The bot wpe-release completed 293 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance/textures/video/tex-2d-rgb-rgb-unsigned_byte.html 106 times [36.2%] -> PASS 187 times [63.8%] -> TEXT -- The bot wpe-release completed 288 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance2/query/occlusion-query.html 51 times [17.7%] -> TIMEOUT 236 times [81.9%] -> TIMEOUT TEXT -- The bot wpe-release completed 282 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance2/textures/canvas_sub_rectangle/tex-2d-rgb5_a1-rgba-unsigned_short_5_5_5_1.html 281 times [99.6%] -> PASS 1 times [0.4%] -> TIMEOUT -- The bot wpe-release completed 281 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance2/transform_feedback/transform_feedback.html 45 times [16.0%] -> TIMEOUT 236 times [84.0%] -> TIMEOUT TEXT -- The bot wpe-release completed 293 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance/canvas/drawingbuffer-static-canvas-test.html 291 times [99.3%] -> PASS 2 times [0.7%] -> TEXT PASS -- The bot wpe-release completed 293 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance/context/context-release-upon-reload.html 289 times [98.6%] -> PASS 4 times [1.4%] -> TEXT PASS -- The bot wpe-release completed 272 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.y/conformance2/transform_feedback/transform_feedback.html 236 times [86.8%] -> TIMEOUT TEXT 36 times [13.2%] -> TIMEOUT

I'm filtering out this tests that have a high pass rate (98-99%) The bot wpe-release completed 293 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance/limits/gl-min-textures.html 288 times [98.3%] -> PASS 5 times [1.7%] -> TEXT -- The bot wpe-release completed 282 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance2/textures/canvas_sub_rectangle/tex-2d-rgb5_a1-rgba-unsigned_short_5_5_5_1.html 281 times [99.6%] -> PASS 1 times [0.4%] -> TIMEOUT -- The bot wpe-release completed 293 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance/canvas/drawingbuffer-static-canvas-test.html 291 times [99.3%] -> PASS 2 times [0.7%] -> TEXT PASS -- The bot wpe-release completed 293 runs on the interval [259359@main-260782@main] Frecuency of results for test: webgl/2.0.0/conformance/context/context-release-upon-reload.html 289 times [98.6%] -> PASS 4 times [1.4%] -> TEXT PASS --

Closing as duplicated. Let's use bug 251107 to track the flakies and failures for WebGL2 tests *** This bug has been marked as a duplicate of bug 251107 ***