Tab bar support for ZWJ emojis

I discovered a funny issue when using ZWJ emoji in a filename. The filename field in the left panel of the UI supports ZWJ emojis as single characters, but the tab bar doesn’t.

So, the first emoji in the fallback sequence is assigned as the favicon for the tab item. In the screenshot above, I’m using the new phoenix ZWJ emoji in the filename, which falls back to 🐦 🔥 . So, 🐦 is assigned as the file favicon.

Not a big deal, but kind of confusing that the favicon in the tab bar doesn’t match the emoji in the filename.