Support math rendering on MFM (#3260)

src/client/app/common/views/components/formula.vue

@@ -0,0 +1,26 @@
+<template>
+<span v-html="compiledFormula"></span>
+</template>
+
+<script lang="ts">
+import Vue from 'vue';
+import * as katex from 'katex';
+
+export default Vue.extend({
+	props: {
+		formula: {
+			type: String,
+			required: true
+		}
+	},
+	computed: {
+		compiledFormula(): any {
+			return katex.renderToString(this.formula);
+		}
+	}
+});
+</script>
+
+<style>
+@import "../../../../../../node_modules/katex/dist/katex.min.css";
+</style>