Added execution abortion on a missing anchorNode

Author: oleksandr-danylchenko

packages/text-annotator/src/SelectionHandler.ts

@@ -77,10 +77,25 @@ export const SelectionHandler = (
   const onSelectionChange = debounce((evt: Event) => {
     const sel = document.getSelection();
 
-    // This is to handle cases where the selection is "hijacked" by another element
-    // in a not-annotatable area. A rare case in theory. But rich text editors
-    // will like Quill do it...
-    if (sel?.anchorNode && isNotAnnotatable(sel.anchorNode)) {
+    /**
+     * In iOS when a user clicks on a button, the `selectionchange` event is fired.
+     * However, the generated selection is empty and the `anchorNode` is `null`.
+     * That doesn't give us information about whether the selection is in the annotatable area
+     * or whether the previously selected text was dismissed.
+     * Therefore - we should bail out from such a range processing.
+     *
+     * @see https://github.com/recogito/text-annotator-js/pull/164#issuecomment-2416961473
+     */
+    if (!sel?.anchorNode) {
+      return;
+    }
+
+    /**
+     * This is to handle cases where the selection is "hijacked" by another element
+     * in a not-annotatable area. A rare case in theory. But rich text editors
+     * will like Quill do it...
+     */
+    if (isNotAnnotatable(sel.anchorNode)) {
       currentTarget = undefined;
       return;
     }