Safari 10 Css.supports('display', 'contents') Returns True Even Though It Is Not Supported?

According to CanIUse.com, display:contents has some support across browsers. https://caniuse.com/#feat=css-display-contents I would like to enable the feature in browsers which sup

Solution 1:

Here's a solution:

@supports (display: contents) and (not (-webkit-flow-from: main)) {
  /**/
}

the display: contents-check only raises a false flag up to Safari 11, so I've been scrolling through the CSS values on caniuse and found CSS Regions, which is only supported by MS browsers up to Edge 18 (the last version that doesn't use Chrome's rendering engine) and Safari versions up to 11.IE doesn't support @supports and Edge doesn't support -webkit-flow-from.

I haven't tested this, by the way, since I don't own any Apple products. If someone could do that, that would be great.