Replace TinyMCE UI pt font sizes with px.

frontend/src/components/Editor.vue

@@ -195,6 +195,7 @@ export default {
                   alignleft aligncenter alignright alignjustify |
                   bullist numlist table image | outdent indent | link hr removeformat |
                   code fullscreen help`,
+        fontsize_formats: '10px 11px 12px 14px 15px 16px 18px 24px 36px',
         skin: false,
         content_css: false,
         content_style: `