diff --git a/apps/studio/src/orisys_studio/ui/force_plots.py b/apps/studio/src/orisys_studio/ui/force_plots.py
index 2b4c7a7..ec8e651 100644
--- a/apps/studio/src/orisys_studio/ui/force_plots.py
+++ b/apps/studio/src/orisys_studio/ui/force_plots.py
@@ -1027,11 +1027,23 @@ class ForcePlotsPanel(QFrame):
         for cursor in self.cursors:
             cursor.setMovable(bool(browsing))
 
-    def _on_cursor_dragged(self) -> None:
-        """The shared cursor is a timeline control while browsing."""
+    def _on_cursor_dragged(self, cursor=None) -> None:
+        """The shared cursor is a timeline control while browsing.
+
+        Each subplot carries its own copy of the same cursor and any of them can be
+        dragged, so the signal names the one that moved. Reading ``cursors[0]`` instead
+        made only the first subplot work: dragging FX or FY re-read FN's already-current
+        value, judged it unchanged and returned, leaving the other two subplots behind.
+        """
         if self._syncing or self._mode != "browse":
             return
-        value = float(self.cursors[0].value())
+        # ``sigPositionChanged`` emits the line that moved; ``sender()`` covers a
+        # pyqtgraph that emits no argument. A direct call with neither falls back to the
+        # first subplot, which is the only cursor a caller could mean.
+        line = cursor if cursor is not None else self.sender()
+        if line is None:
+            line = self.cursors[0]
+        value = float(line.value())
         if value == self._cursor_t:
             return
         self.pause_playback()
diff --git a/apps/studio/tests/test_ui_smoke.py b/apps/studio/tests/test_ui_smoke.py
index b63aae4..6016f23 100644
--- a/apps/studio/tests/test_ui_smoke.py
+++ b/apps/studio/tests/test_ui_smoke.py
@@ -1452,6 +1452,21 @@ def test_the_charts_zoom_and_pan_in_every_view(make_window):
     QApplication.processEvents()
     assert [round(cursor.value(), 2) for cursor in panel.cursors] == [1.25] * 3
     assert moved and moved[-1] == 1.25, "the cursor drag did not notify the replay"
+
+    # Every subplot carries the same cursor, so every one of them is the control.
+    # Dragging FX or FY used to re-read FN's already-current value, judge it unchanged and
+    # return — only the first subplot moved the other two.
+    for index in (1, 2):
+        moved.clear()
+        target = round(1.5 + index * 0.1, 2)
+        panel.cursors[index].setValue(target)
+        QApplication.processEvents()
+        assert [round(cursor.value(), 2) for cursor in panel.cursors] == [target] * 3, (
+            f"dragging subplot {index}'s cursor did not move the other two"
+        )
+        assert moved and round(moved[-1], 2) == target, (
+            f"dragging subplot {index}'s cursor did not notify the replay"
+        )
     _finish(window, stuck)