diff --git a/direct/src/dist/commands.py b/direct/src/dist/commands.py
index ba0d367254..48e2bd70b6 100644
--- a/direct/src/dist/commands.py
+++ b/direct/src/dist/commands.py
@@ -618,12 +618,16 @@ class build_apps(setuptools.Command):
                     rootdir = wf.split(os.path.sep, 1)[0]
                     search_path.append(os.path.join(whl, rootdir, '.libs'))
 
+                    # Also look for eg. numpy.libs or Pillow.libs in the root
+                    whl_name = os.path.basename(whl).split('-', 1)[0]
+                    search_path.append(os.path.join(whl, whl_name + '.libs'))
+
                     # Also look for more specific per-package cases, defined in
                     # PACKAGE_LIB_DIRS at the top of this file.
-                    whl_name = os.path.basename(whl).split('-', 1)[0]
                     extra_dirs = PACKAGE_LIB_DIRS.get(whl_name, [])
                     for extra_dir in extra_dirs:
                         search_path.append(os.path.join(whl, extra_dir.replace('/', os.path.sep)))
+
             return search_path
 
         def create_runtime(appname, mainscript, use_console):
diff --git a/panda/src/display/graphicsStateGuardian.cxx b/panda/src/display/graphicsStateGuardian.cxx
index 911ef621da..f26104449a 100644
--- a/panda/src/display/graphicsStateGuardian.cxx
+++ b/panda/src/display/graphicsStateGuardian.cxx
@@ -1985,7 +1985,14 @@ fetch_specified_texture(Shader::ShaderTexSpec &spec, SamplerState &sampler,
         Light *light_obj = light.node()->as_light();
         nassertr(light_obj != nullptr, nullptr);
 
-        PT(Texture) tex = get_shadow_map(light);
+        PT(Texture) tex;
+        LightLensNode *lln = DCAST(LightLensNode, light.node());
+        if (lln != nullptr && lln->_shadow_caster) {
+          tex = get_shadow_map(light);
+        } else {
+          tex = get_dummy_shadow_map((Texture::TextureType)spec._desired_type);
+        }
+
         if (tex != nullptr) {
           sampler = tex->get_default_sampler();
         }
diff --git a/panda/src/pgraph/textureAttrib.cxx b/panda/src/pgraph/textureAttrib.cxx
index 0184f1825c..d08344fc4d 100644
--- a/panda/src/pgraph/textureAttrib.cxx
+++ b/panda/src/pgraph/textureAttrib.cxx
@@ -109,12 +109,18 @@ add_on_stage(TextureStage *stage, Texture *tex, int override) const {
   nassertr(tex != nullptr, this);
 
   TextureAttrib *attrib = new TextureAttrib(*this);
-  Stages::iterator si = attrib->_on_stages.insert(StageNode(stage)).first;
-  (*si)._override = override;
-  (*si)._texture = tex;
-  (*si)._implicit_sort = attrib->_next_implicit_sort;
-  (*si)._has_sampler = false;
-  ++(attrib->_next_implicit_sort);
+  auto result = attrib->_on_stages.insert(StageNode(stage));
+  StageNode &sn = *result.first;
+  sn._override = override;
+  sn._texture = tex;
+  sn._has_sampler = false;
+
+  // Only bump this if it doesn't already have the highest implicit sort.
+  // This prevents replacing a texture from creating a unique TextureAttrib.
+  if (result.second || sn._implicit_sort + 1 != attrib->_next_implicit_sort) {
+    sn._implicit_sort = attrib->_next_implicit_sort;
+    ++(attrib->_next_implicit_sort);
+  }
 
   return return_new(attrib);
 }
@@ -128,13 +134,19 @@ add_on_stage(TextureStage *stage, Texture *tex, const SamplerState &sampler, int
   nassertr(tex != nullptr, this);
 
   TextureAttrib *attrib = new TextureAttrib(*this);
-  Stages::iterator si = attrib->_on_stages.insert(StageNode(stage)).first;
-  (*si)._override = override;
-  (*si)._texture = tex;
-  (*si)._sampler = sampler;
-  (*si)._implicit_sort = attrib->_next_implicit_sort;
-  (*si)._has_sampler = true;
-  ++(attrib->_next_implicit_sort);
+  auto result = attrib->_on_stages.insert(StageNode(stage));
+  StageNode &sn = *result.first;
+  sn._override = override;
+  sn._texture = tex;
+  sn._sampler = sampler;
+  sn._has_sampler = true;
+
+  // Only bump this if it doesn't already have the highest implicit sort.
+  // This prevents replacing a texture from creating a unique TextureAttrib.
+  if (result.second || sn._implicit_sort + 1 != attrib->_next_implicit_sort) {
+    sn._implicit_sort = attrib->_next_implicit_sort;
+    ++(attrib->_next_implicit_sort);
+  }
 
   return return_new(attrib);
 }
diff --git a/tests/pgraph/test_textureattrib.py b/tests/pgraph/test_textureattrib.py
index 2be4b479f3..82ec9912f5 100644
--- a/tests/pgraph/test_textureattrib.py
+++ b/tests/pgraph/test_textureattrib.py
@@ -89,25 +89,6 @@ def test_textureattrib_compose_both():
     assert stage3 in tattr3.on_stages
 
 
-def test_textureattrib_implicit_sort():
-    # Tests that two TextureStages with same sort retain insertion order.
-    tattr1 = core.TextureAttrib.make()
-    tattr1 = tattr1.add_on_stage(stage1, tex1)
-    tattr1 = tattr1.add_on_stage(stage2, tex2)
-
-    assert tattr1.get_on_stage(0) == stage1
-    assert tattr1.get_on_stage(1) == stage2
-
-    tattr2 = core.TextureAttrib.make()
-    tattr2 = tattr1.add_on_stage(stage2, tex2)
-    tattr2 = tattr1.add_on_stage(stage1, tex1)
-
-    assert tattr2.get_on_stage(0) == stage2
-    assert tattr2.get_on_stage(1) == stage1
-
-    assert tattr1.compare_to(tattr2) == -tattr2.compare_to(tattr1)
-
-
 def test_textureattrib_compose_alloff():
     # Tests a case in which a child node disables all textures.
     tattr1 = core.TextureAttrib.make()
@@ -124,6 +105,37 @@ def test_textureattrib_compose_alloff():
     assert tattr3.has_all_off()
 
 
+def test_textureattrib_implicit_sort():
+    # Tests that two TextureStages with same sort retain insertion order.
+    tattr1 = core.TextureAttrib.make()
+    tattr1 = tattr1.add_on_stage(stage1, tex1)
+    tattr1 = tattr1.add_on_stage(stage2, tex2)
+
+    assert tattr1.get_on_stage(0) == stage1
+    assert tattr1.get_on_stage(1) == stage2
+
+    tattr2 = core.TextureAttrib.make()
+    tattr2 = tattr2.add_on_stage(stage2, tex2)
+    tattr2 = tattr2.add_on_stage(stage1, tex1)
+
+    assert tattr2.get_on_stage(0) == stage2
+    assert tattr2.get_on_stage(1) == stage1
+
+    assert tattr1.compare_to(tattr2) == -tattr2.compare_to(tattr1)
+
+
+def test_textureattrib_replace():
+    # Test that replacing a texture doesn't create a unique TextureAttrib.
+    tattr1 = core.TextureAttrib.make()
+    tattr1 = tattr1.add_on_stage(stage1, tex1)
+
+    tattr2 = tattr1.add_on_stage(stage1, tex1)
+
+    assert tattr1.get_num_on_stages() == 1
+    assert tattr2.get_num_on_stages() == 1
+    assert tattr1.compare_to(tattr2) == 0
+
+
 def test_textureattrib_compare():
     tattr1 = core.TextureAttrib.make()
     tattr2 = core.TextureAttrib.make()