thonk.user.css

/* ==UserStyle==
@name           thonk
@namespace      comp500
@version        1.0.0
@description    Replaces GitHub's Confused emoji with thonk
@author         comp500
==/UserStyle== */

/*
Doesn't work for some reason
g-emoji[alias="thinking_face"] > img, g-emoji[alias="confused"] > img {
	content: url("https://raw.githubusercontent.com/quat1024/quat1024.github.io/master/thonk.png");
}
*/

@-moz-document regexp("^https?://((gist|guides|help|launch-editor|raw|resources|status|developer)\\.)?github\\.com/((?!generated_pages/preview).)*$") {
	g-emoji[alias="thinking_face"], g-emoji[alias="confused"] {
		background-image: url("https://raw.githubusercontent.com/quat1024/quat1024.github.io/master/thonk.png");
		width: 23px;
		display: inline-block;
		height: 22px;
		background-size: contain;
		background-repeat: no-repeat;
		font-size: 0;
	}
}