On Mon, Feb 25, 2019 at 8:49 AM Philip Jägenstedt <foolip@chromium.org> wrote:

I'd like to point out right away that diagnosing reftest failures is
currently cumbersome because we don't store the screenshots. This is
also a work in progress:
https://docs.google.com/document/d/1IhZa4mrjK1msUMhtamKwKJ_HhXD-nqh_4-BcPWM6soQ/edit?usp=sharing

Until that has launched, I would recommend ignoring reftest failures
if the cause of failure isn't obvious.
  

Great news! Reftest screenshots are now available on wpt.fyi. No more guesswork for why a reftest fails!

For example, this is one of the Safari-only reftest failures you can find using the search link posted earlier. Now you can click the "compare" button (you might need to force-reload the page to see it) to view the screenshots. This example looks like a genuine failure, while some others are probably caused by font antialiasing/kerning (they should most likely use the Ahem font instead).

We are also working on another feature to triage the failures (e.g. to mark a test as a genuine failure and link it to bug trackers, or as flaky/broken). Stay tuned!