Replace Twitter icon with X

[jasmussen]

We currently show this:

Let's update this to the new logo chosen by the company.

I know that a PR has been merged to the Gutenberg plugin to add the icon, let's do that as soon as it's possible as this will also update the link text.

Until then, and if that takes more than a couple of days to do, let's apply a temporary hack. You can use this codepen, but the pertinent bit is this:

.wp-social-link-twitter {
	background: url(https://cldup.com/GnkaLzBcia.svg) no-repeat;
	background-size: 100%;
	
	svg {
		visibility: hidden;
	}
}

That cloudup link is just to show it working in the codepen, but you can snatch the SVG code here. X.svg:

<svg width="24" height="24" viewBox="0 0 24 24" version="1.1" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false"><path d="M13.982 10.622 20.54 3h-1.554l-5.693 6.618L8.745 3H3.5l6.876 10.007L3.5 21h1.554l6.012-6.989L15.868 21h5.245l-7.131-10.378Zm-2.128 2.474-.697-.997-5.543-7.93H8l4.474 6.4.697.996 5.815 8.318h-2.387l-4.745-6.787Z"></path></svg>

[adamwoodnz]

This is part of the global footer, hence the transfer to the mu-plugins repo.

[StevenDufresne]

@ndiego has a pr for this: #461

[ndiego]

Yeah 🤞 Gutenberg 16.8 doesn't break things like 16.7, and we can merge #461 later this week.