Got a question that's not answered here? Get in touch via the Motion One GitHub repo.
There's no fundamental technical reason but there's no plans to bring it to other browsers at this time.
Are the elements involved in the animation still part of the DOM? You can check by clicking the element's magnifying glass button. If it doesn't link through to the Elements tab, the element has been removed.
To fix, temporarily amend your code so that element's are kept in the DOM after the animation has completed.
Sometimes a seemingly simple animation will appear in the timeline with many keyframes spaced evenly apart, perhaps every 10ms or so.
This is almost always a result of keyframe pregeneration, a technique used by libraries like Svelte and Motion One to create spring and other animations not natively supported by browsers.
For Motion One, pregenerated animations will be natively supported in an upcoming updated, so you can edit and add your own springs. For other libraries, this will be more difficult to support, but will be looked into.