fix: guard link recognizer against stale/detached node in _tapNodeLink

CHANGELOG.md

@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Fixed an issue where bullet points became visually detached from the text body when toggling text direction formatting (RTL) by locking the list leading block to the editor's base text direction.
 - Fixed typed text being inserted at the previous caret position on Android after moving the caret with a tap/mouse by keeping the platform IME's editing state in sync with the selection even when the keyboard is hidden.
+- Fixed a `Null check operator used on a null value` crash in `_TextLineState._tapNodeLink`/`_longPressLink` when a cached link gesture recognizer fires after the document mutates: the captured node can be detached or have lost its `link` attribute by the time the tap is swept by the gesture arena (`_linkRecognizers` is not cleared when the line content changes), so the link attribute is now read defensively instead of force-unwrapped.
 
 ### Removed
 

lib/src/editor/widgets/text/text_line.dart

@@ -698,7 +698,12 @@ class _TextLineState extends State<TextLine> {
   }
 
   void _tapNodeLink(Node node) {
-    final link = node.style.attributes[Attribute.link.key]!.value;
+    // The recognizer's onTap closure captures a specific node, but the cached
+    // recognizer outlives document mutations (_linkRecognizers is not cleared
+    // when the line content changes). By the time a queued tap is swept by the
+    // gesture arena, the captured node may be detached or have lost its link
+    // attribute, so read it defensively instead of force-unwrapping.
+    final link = node.style.attributes[Attribute.link.key]?.value;
 
     _tapLink(link);
   }
@@ -723,7 +728,12 @@ class _TextLineState extends State<TextLine> {
   }
 
   Future<void> _longPressLink(Node node) async {
-    final link = node.style.attributes[Attribute.link.key]!.value!;
+    // See _tapNodeLink: the captured node may no longer carry a link attribute
+    // by the time the gesture fires, so guard instead of force-unwrapping.
+    final link = node.style.attributes[Attribute.link.key]?.value;
+    if (link == null) {
+      return;
+    }
     final action = await widget.linkActionPicker(node);
     switch (action) {
       case LinkMenuAction.launch: