diff --git a/src/blenderbim/blenderbim/bim/module/drawing/operator.py b/src/blenderbim/blenderbim/bim/module/drawing/operator.py
index 61b0141db1..20e5c2ae38 100644
--- a/src/blenderbim/blenderbim/bim/module/drawing/operator.py
+++ b/src/blenderbim/blenderbim/bim/module/drawing/operator.py
@@ -521,7 +521,7 @@ class CreateDrawing(bpy.types.Operator):
         # https://stackoverflow.com/questions/36018627/sorting-child-elements-with-lxml-based-on-attribute-value
         group = root.find("{http://www.w3.org/2000/svg}g")
         # group[:] = sorted(group, key=lambda e : "projection" in e.get("class"))
-        if group and len(group):
+        if group is not None:
             group[:] = reversed(group)
 
     def canonicalise_class_name(self, name):
diff --git a/src/blenderbim/docs/devs/system_support.rst b/src/blenderbim/docs/devs/system_support.rst
index cef3680a14..5d53cc379a 100644
--- a/src/blenderbim/docs/devs/system_support.rst
+++ b/src/blenderbim/docs/devs/system_support.rst
@@ -15,3 +15,21 @@ be no guarantee of the uptime or stability of these builds.
 
 Other system specifications match the `Blender Requirements
 <https://www.blender.org/download/requirements/>`_.
+
+Add-on compatibility
+--------------------
+
+The BlenderBIM Add-on is a non-trivial add-on. By turning Blender into a
+graphical front-end to a native IFC authoring platform, some fundamental Blender
+features (such as object deletion and object duplication) have been patched.
+
+Other add-ons may no longer work as intended when the BlenderBIM Add-on is
+enabled, or vice versa, the BlenderBIM Add-on may no longer work as intended
+when other add-ons are enabled.
+
+Known scenarios which will lead to add-on incompatibility include:
+
+- The add-on overrides object deletion or duplication
+- The add-on uses object deletion or duplication macros with dictionary
+  override. Note that this is also deprecated in Blender, so the other add-on
+  should be updated to fix this.