One thing to consider is that we'll want to run on both the emulator for volume and physical device(s) for hardware coverage. I would suspect the current version of the emulator used in CI would not support vulkan, as it's rather old.
Bug 1836811 Comment 2 Edit History
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One thing to consider is that we'll want to run on both the emulator for volume and less frequently on physical device(s) for hardware coverage. I would suspect the current version of the emulator used in CI would not support vulkan, as it's rather old.