Add a comment about possible performance issues

service.js

@@ -254,8 +254,7 @@ class BesService {
       BesService.getNodesInRange(range).forEach(el => {
         if (
           el === hostElement ||
-          Array.from(hostElement.childNodes).includes(el) ||
-          hostElement.contains(el)
+          Array.from(hostElement.childNodes).includes(el)
         ) {
           blockElements.add(service.getBlockParent(el))
         }
@@ -266,6 +265,8 @@ class BesService {
       service.removeChild(block)
     })
     // Not a nice way to do it, but it works for now the repositionMistakes function is called before the DOM updates are finished.
+    // If users will experience performance issues, we can consider debouncing this function.
+    // The lagginess becomes noticeable if the text is long and has many grammar mistakes.
     setTimeout(() => {
       service.repositionMistakes()
     }, 0)