Bug 248865

WebGL via Metal fails to load and render multiple WebGL 1 based web pages.
The page either doesn't load or takes a long time to load. If it loads, eventually only some graphics will render but most common, the page is rendered black.
Turning off WebGL via Metal restores previous experience (macOS 12.6 or earlier).

Issue found on a MacBook Air (Intel i7) from 2020 running macOS 13.0.1 (Ventura) and Safari 16.1.

The issue is similar but not exactly same as to that of described here which was resolved for Monteray.
https://support.google.com/maps/thread/182536169

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Steps to reproduce issue:

1. Go to www.thunderkick.com and click on the first "Play Game" button shown.
2. The game pops up as a modal and starts to load.
3. The load never finishes or it results in a (commonly) black screen.

Steps to work-around the issue:
1. Go into Developer and Experimental Features and turn off WebGL via Metal.
2. Go to www.thunderkick.com and click on the first "Play Game" button shown.
2. The game pops up as a modal and starts to load.
4. The load never completes reasonably fast and the game is displayed properly.

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