diff --git a/src/black/linegen.py b/src/black/linegen.py
index 8846d77..2bbad96 100644
--- a/src/black/linegen.py
+++ b/src/black/linegen.py
@@ -778,10 +778,7 @@ def bracket_split_build_line(
                     break
 
     leaves_to_track: Set[LeafID] = set()
-    if (
-        Preview.handle_trailing_commas_in_head in original.mode
-        and component is _BracketSplitComponent.head
-    ):
+    if component is _BracketSplitComponent.head:
         leaves_to_track = get_leaves_inside_matching_brackets(leaves)
     # Populate the line
     for leaf in leaves:
diff --git a/src/black/mode.py b/src/black/mode.py
index 136f5c5..3cc7412 100644
--- a/src/black/mode.py
+++ b/src/black/mode.py
@@ -149,7 +149,6 @@ def supports_feature(target_versions: Set[TargetVersion], feature: Feature) -> b
 class Preview(Enum):
     """Individual preview style features."""
 
-    handle_trailing_commas_in_head = auto()
     long_docstring_quotes_on_newline = auto()
     normalize_docstring_quotes_and_prefixes_properly = auto()
     one_element_subscript = auto()