Sculpt: fix missing NULL check

release/scripts/startup/bl_ui/properties_paint_common.py

@@ -27,6 +27,7 @@ builtin_channel_categories = ["Cloth Tool",
     "Color",
     "Clay",
     "Pose Tool",
+    "Smear",
     "Basic",
     "Smoothing",
     "Stroke",

source/blender/blenkernel/intern/dyntopo.c

@@ -3869,6 +3869,10 @@ static void pbvh_bmesh_collapse_edge(PBVH *pbvh,
         do {
           BMLoop *l2 = e2->l;
 
+          if (!l2) {
+            continue;
+          }
+
           do {
             BMLoop *l3 = l2->v != v ? l2->next : l2;