Skip custom emojis when they match a Unicode emoji's shortcode

app/soapbox/reducers/custom_emojis.js

@@ -1,14 +1,22 @@
-import { List as ImmutableList, fromJS as ConvertToImmutable } from 'immutable';
+import { List as ImmutableList, fromJS } from 'immutable';
 import { CUSTOM_EMOJIS_FETCH_SUCCESS } from '../actions/custom_emojis';
-import { search as emojiSearch } from '../features/emoji/emoji_mart_search_light';
-import { buildCustomEmojis } from '../features/emoji/emoji';
+import { emojis as emojiData } from 'soapbox/features/emoji/emoji_mart_data_light';
 
-const initialState = ImmutableList([]);
+const initialState = ImmutableList();
+
+const importEmojis = (state, emojis) => {
+  return fromJS(emojis).filter(emoji => {
+    // If a custom emoji has the shortcode of a Unicode emoji, skip it.
+    // Otherwise it breaks EmojiMart.
+    // https://gitlab.com/soapbox-pub/soapbox-fe/-/issues/610
+    const shortcode = emoji.get('shortcode', '').toLowerCase();
+    return !emojiData[shortcode];
+  });
+};
 
 export default function custom_emojis(state = initialState, action) {
-  if(action.type === CUSTOM_EMOJIS_FETCH_SUCCESS) {
-    state = ConvertToImmutable(action.custom_emojis);
-    emojiSearch('', { custom: buildCustomEmojis(state) });
+  if (action.type === CUSTOM_EMOJIS_FETCH_SUCCESS) {
+    return importEmojis(state, action.custom_emojis);
   }
 
   return state;