diff --git a/meshterm/ui/node_detail_screen.py b/meshterm/ui/node_detail_screen.py
index 3152f82..40cd2cf 100644
--- a/meshterm/ui/node_detail_screen.py
+++ b/meshterm/ui/node_detail_screen.py
@@ -75,6 +75,7 @@ from .pathgraph import (
     LabelOf,
     LabelRgbOf,
     PathLayer,
+    _coalesce_prefixes,
     bidir_clusters,
     render_path_graph,
 )
@@ -649,7 +650,11 @@ class NodeDetailScreen(Screen):
         # A node keeps its name hue only while it sits on the selected route (its endpoints
         # always do); every other node in the fan fades its label to the same grey its line
         # went, so the picture reads as *this* route rather than the whole tangle.
-        on_route = set(rv.routes[sel].draw) | {SRC_NODE, DST_NODE}
+        # Membership is decided in the graph's own id space: the widget folds a short hop
+        # into the wide id it can only be among these routes (a 1-byte trace hop beside the
+        # same relay's full contact id), so the raw draw hops would grey the very marker the
+        # selected line rides through.
+        on_route = set(_coalesce_prefixes(layers)[sel].hops) | {SRC_NODE, DST_NODE}
         base_rgb = rv.label_rgb_of
         assert base_rgb is not None
 
diff --git a/tests/test_node_detail.py b/tests/test_node_detail.py
index d141a41..3642d87 100644
--- a/tests/test_node_detail.py
+++ b/tests/test_node_detail.py
@@ -572,6 +572,37 @@ def test_node_detail_enter_on_a_route_row_opens_its_trace() -> None:
     assert resolved == ["trace"] and screen.selected_spec() == "a1,f2,a1"
 
 
+def test_route_labels_light_through_a_coalesced_hop() -> None:
+    """A route drawn from a short hop id lights the wide marker the graph folds it into.
+
+    Route evidence reaches the page at mixed hash widths — a 1-byte trace hop (``3d``)
+    beside the same relay's full id on a sibling route. The graph coalesces the short id
+    into the one wide marker, so the label muting must test membership against the *drawn*
+    ids: keyed on the raw draw hops, the selected route's own relay rendered muted while
+    the white line rode straight through it (the TSFCT SUTTON-680M report).
+    """
+    lit: list[str] = []
+
+    def base_rgb(node: str) -> tuple[int, int, int]:
+        lit.append(node)  # the stage's muting wrapper only consults us for on-route nodes
+        return (200, 200, 200)
+
+    routes = _RoutesView(
+        routes=[
+            _Route(draw=("bf61f2fb1d9e", "3d63c6429436"), spec="s0", row=Text("wide")),
+            _Route(draw=("bf61f2fb1d9e", "3d"), spec="s1", row=Text("short")),
+        ],
+        glyph_of=lambda n: ("●", "#ffffff"),
+        label_of=lambda n: n[:2],
+        label_rgb_of=base_rgb,
+    )
+    screen = _screen(routes=routes, tabs=[_Tab("Routes", "routes")])
+    screen.note_viewport(30)
+    screen.handle("down")  # select the short-hop route
+    screen.render_body(72)
+    assert "3d63c6429436" in lit  # the relay it rides through keeps its hue
+
+
 def test_node_detail_route_list_windows_inside_the_page() -> None:
     """With more routes than fit, the list windows with edge markers — the graph and the
     action rows never leave the screen, however many routes a busy node has."""