diff --git a/xblocks_contrib/html/__init__.py b/xblocks_contrib/html/__init__.py
index 5b8118f9..0fe36653 100644
--- a/xblocks_contrib/html/__init__.py
+++ b/xblocks_contrib/html/__init__.py
@@ -2,4 +2,4 @@
 Init for the HtmlBlock.
 """
 
-from .html import HtmlBlock
+from .html import HtmlBlock, HtmlBlockMixin
diff --git a/xblocks_contrib/html/html.py b/xblocks_contrib/html/html.py
index ab1d9fa3..282e6292 100644
--- a/xblocks_contrib/html/html.py
+++ b/xblocks_contrib/html/html.py
@@ -143,13 +143,12 @@ def stringify_children(node):
 # This makes our block more resilient. It won't crash in test environments
 # where the user service might not be available.
 @XBlock.wants("user")
-class HtmlBlock(LegacyXmlMixin, XBlock):
+class HtmlBlockMixin(LegacyXmlMixin, XBlock):
     """
-    The HTML XBlock.
+    The HTML XBlock mixin.
+    This provides the base class for all Html-ish blocks (including the HTML XBlock).
     """
 
-    # Indicates that this XBlock has been extracted from edx-platform.
-    is_extracted = True
     display_name = String(
         display_name=_("Display Name"),
         help=_("The display name for this component."),
@@ -565,3 +564,12 @@ def definition_to_xml(self, resource_fs):
     def non_editable_metadata_fields(self):
         """`use_latex_compiler` should not be editable in the Studio settings editor."""
         return super().non_editable_metadata_fields + [HtmlBlock.xml_attributes, HtmlBlock.use_latex_compiler]
+
+
+class HtmlBlock(HtmlBlockMixin):  # pylint: disable=abstract-method
+    """
+    The HTML XBlock.
+    """
+
+    # Indicates that this XBlock has been extracted from edx-platform.
+    is_extracted = True