🚫 Blocking flutter/cocoon#3487, which is why this is P1 (border-line P0, IMO).

I have a requested outcome, but I'm not prescriptive about getting there: the screenshots emitted by web tests on Skia Gold on the engine tree should not be unstable day-to-day, and should not block the tree (#143352).

@yjbanov and @mdebbar seem to think it's an infra issue, though @yjbanov later wrote:

I'd be OK with any of the following quick fixes:

• Tweak matching algorithms specifically for Safari
• Enforce a specific drone type on LUCI (no flipping between x86 and Arm, for example)
• Disable Safari + HTML golden tests

While the last option is my least favorite, but if this is blocking the tree and other options are not helping or too costly, then maybe that's the way to go. We already get decent coverage for the HTML renderer from other browsers.

Any of these would be OK for me, assuming they fix the instability.

Background

Most days, I open up flutter-engine on Skia gold, and see something like the following:

These are all (AFAICT), (1) Web tests, and (2) Safari tests. For example: