Fix threaded mode not resetting quote (#3284)

app/javascript/flavours/glitch/reducers/compose.js

@@ -213,6 +213,7 @@ function continueThread (state, status) {
     map.set('focusDate', new Date());
     map.set('caretPosition', null);
     map.set('preselectDate', new Date());
+    map.set('quoted_status_id', null);
   });
 }