Spinner indicator not visible in Safari in beta 63

[jaredcwhite]

This is the first time I've seen the problem, not sure if it's only affected in beta 63. The animation seems to be working, but the actual indicator isn't showing, so it's just a static ring.

[claviska]

Ha! I'm literally looking at this right now. I broke it when I simplified the animation. Safari is finicky with animating SVGs, but this time Firefox is also affected.

[claviska]

This seems like a Safari bug. You should see a half circle in blue: https://codepen.io/claviska/pen/poWpPbY

Actual result in Safari:

Note that if you remove the track width (which is in pixels) from here it works: calc(50% - var(--track-width) / 2)

Perhaps Safari doesn't like [certain?] mixed units in stroke-dasharray. Both Chrome and Firefox render it correctly:

[claviska]

I've simplified the math to use percentages. This makes it work in Safari, but it doesn't account for the track width. I think this is OK since it's only a matter of pixels and the indicator is animated anyways. It will only be noticeable with a large track width and a small radius, which doesn't really look good anyways.