Add behavior change note for @export_file annotation in Godot 4.4

tutorials/migrating/upgrading_to_godot_4.4.rst

@@ -55,6 +55,23 @@ Method ``post`` adds a new ``count`` optional parameter
 Method ``standardize_locale`` adds a new ``add_defaults`` optional parameter                                              |✔️|                 |✔️ with compat|      |✔️ with compat|      `GH-98972`_
 ========================================================================================================================  ===================  ====================  ====================  ============
 
+**Export annotations**
+
+.. warning::
+
+    The behavior of ``@export_file`` changed in Godot 4.4. When assigning a new value from the Inspector, the path is now stored and returned as a ``uid://`` reference instead of the traditional ``res://`` path. This is a **breaking change** and may cause issues if you're expecting ``res://``-based paths in scripts or serialized files.
+
+    For example, exported arrays of files may now contain a mix of ``uid://`` and ``res://`` paths, especially if they were edited partially in the Inspector.
+
+    In 4.4, the only way to retain the ``res://`` format is to **manually edit** the `.tscn` or `.tres` files in a text editor. Starting in Godot 4.5, a new annotation ``@export_file_path`` can be used to explicitly retain the old behavior and export raw ``res://`` paths.
+
+    Related issues:
+
+    - PR: `Add @export_file_path to export raw paths (no UID) <https://github.com/godotengine/godot/pull/105414>`_
+    - Issue: `@export_file behavior change is breaking <https://github.com/godotengine/godot/issues/11065>`_
+    - See also: `ProjectSettings stores UIDs for file paths <https://github.com/godotengine/godot/pull/104818>`_
+
+
 .. [#f1] Default buffer size in 4.3 is ``1024``.
 
 GUI nodes