Step 1: Figure out what kind of animation. I seem to recall that we fixed one more use case recently.

There's a rotating rect driven by an <animate> element in an SVG that is updated despite its layer being off-screen. It seems we might have to run this, as we don't know the side effects that might be happening. Does anyone have an insight on whether we can not run this code snippet when out of view:

<svg viewBox="0 0 350 350" fill="currentColor" preserveAspectRatio="xMidYMid meet" height="350" width="350" style="vertical-align: middle;">
  <g stroke="none" stroke-width="1" fill="none" fill-rule="evenodd">
    <rect fill="#40e7b8" x="170" y="5" width="10" height="340" opacity="1" transform="rotate(324.353 175 176)">
      <animateTransform attributeName="transform" attributeType="XML" type="rotate" from="0 175 176" to="360 175 176" dur="8s" repeatCount="indefinite">
      </animateTransform>
    </rect>
  </g>
</svg>

To be able to not run it we'd need to know that the target (the <rect>) is not visible (anytime during the animation) or have side-effects (like event-listeners triggered by interval updates - 'begin', 'end', 'repeat*'. None in this case based on the above snippet. Syncbases would also need to be considered, since could affect visible animations.) There's possibly more to it...

Issue 664258 is pretty much the same thing (with similar restrictions.) We also have  issue 377097 , which is a slightly "simpler" version of this.

This issue has been Available for over a year. If it's no longer important or seems unlikely to be fixed, please consider closing it out. If it is important, please re-triage the issue.

Sorry for the inconvenience if the bug really should have been left as Available.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Based on the comments it seems that the plausible improvements are covered in other bugs. So closing this one.