Bugzilla

Here's a feature-detect, if anyone needs it:

```js
const supportsDisplayTransition = (() => {
  let cachedValue = undefined;
  return () => {
    if (cachedValue === undefined) {
      const div = document.createElement('div');
      Object.assign(div.style, {
        width: '2px',
        transition: 'display 1s allow-discrete'
      });
      document.body.append(div);
      div.offsetWidth;
      div.style.display = 'none';
      cachedValue = div.offsetWidth === 2;
    }
    
    return cachedValue;
  };
})();
```

Here's a feature-detect, if anyone needs it:

```js
const supportsDisplayTransition = (() => {
  let cachedValue = undefined;
  return () => {
    if (cachedValue === undefined) {
      const div = document.createElement('div');
      div.style.transition = 'display 1s allow-discrete';
      document.body.append(div);
      const cs = getComputedStyle(div);
      cs.display;
      div.style.display = 'none';
      cachedValue = cs.display !== 'none';
      div.remove();
    }
    
    return cachedValue;
  };
})();
```