i.mce-i-video:before {
    content: "\f19b";
	font: normal 20px/1 dashicons;
}

i.mce-i-button:before {
    content: "\f502";
	font: normal 20px/1 dashicons;
}

i.mce-i-footnote:before {
    content: "\f118";
	font: normal 20px/1 dashicons;
}