[formatter] add 'format-operator-dot' option

to allow disabling the behavior introduced in commit
a79a945494

docs/configuration.rst

@@ -9376,6 +9376,22 @@ Description
         by using a `defaultdict <https://docs.python.org/3/library/collections.html#collections.defaultdict>`__
 
 
+format-operator-dot
+-------------------
+Type
+    ``bool``
+Default
+    ``true``
+Description
+    In standard `Format Strings`_, allow the `dot` operator ``.``
+    to function as a general access operator
+    in addition to regular attribute access.
+
+    * ``obj.attribute``
+    * ``dict.fieldname``
+    * ``list.123``
+
+
 format-separator
 ----------------
 Type

gallery_dl/__init__.py

@@ -120,7 +120,10 @@ def main():
             elif filterenv.startswith("default"):
                 util.compile_expression = util.compile_expression_defaultdict
 
-        # format string separator
+        # format string options
+        if not config.get((), "format-operator-dot", True):
+            from . import formatter
+            formatter._attrgetter = formatter.operator.attrgetter
         if separator := config.get((), "format-separator"):
             from . import formatter
             formatter._SEPARATOR = separator