Safari 12 crashes upon clicking a <select> element that uses Quicksand

A page will crash in MacOS Safari 12 at the moment the user clicks a select element whose font-family is Quicksand.

A reduced test case is below (or visit https://jsfiddle.net/nL1abgwx)
```html

Click here to crash this page

```

Notes:
- The crashing behavior no longer happens if the font is simply switched to Oswald. It seems to only happen with Quicksand.
- Multiple font-weights in the tag appears to be necessary to cause the crashing behavior, not sure why.
- The select element must have `border: 0` because Safari will not apply the font without it (see here: https://css-tricks.com/dropdown-default-styling/#article-header-id-2)