fix(segmentations): Ensure plane viewer label update hook is deleted …

…when viewers are

src/bundles/segmentations/src/__init__.py

@@ -10,7 +10,7 @@
 # including partial copies, of the software or any revisions
 # or derivations thereof.
 # === UCSF ChimeraX Copyright ===
-__version__ = "3.2.5"
+__version__ = "3.2.6"
 
 from chimerax.core import runtime_env_is_chimerax_app as _runtime_env_is_chimerax_app
 from chimerax.segmentations.segmentation import Segmentation, open_grids_as_segmentation

src/bundles/segmentations/src/ui/label.py

@@ -598,10 +598,10 @@ def __init__(
         self.outline_width = outline_width
         self.scalebar_width = scalebar_width  # Angstroms
         self.scalebar_height = scalebar_height  # Pixels
-        self.drawing = d = LabelModel(session, self)
-        d.display = visibility
-        self.lb = Labels(session, view)
-        self.lb.add_label(self)
+        self.drawing = LabelModel(session, self)
+        self.drawing.display = visibility
+        self.labels = Labels(session, view)
+        self.labels.add_label(self)
 
     def update_drawing(self):
         d = self.drawing

src/bundles/segmentations/src/ui/orthoplanes.py

@@ -614,6 +614,8 @@ def _onSliderMoved(self):
     def close(self):
         # TODO: why does this call make it crash?
         # self.setParent(None)
+        # TODO: Clean up the Label(s) interface
+        self.label.labels.delete()
         self.label.delete()
         chimerax.segmentations.triggers.remove_handler(
             self.guideline_visibility_handler