handle libraries (other than taipy) in HTML renderer

src/taipy/gui/_renderers/_html/factory.py

@@ -19,5 +19,5 @@ class _HtmlFactory(_Factory):
     def create_element(gui, namespace: str, control_type: str, all_properties: t.Dict[str, str]) -> t.Tuple[str, str]:
         builder_html = _Factory.call_builder(gui, f"{namespace}.{control_type}", all_properties, True)
         if builder_html is None:
-            return f"<div>INVALID SYNTAX - Control is '{namespace}:{control_type}'", "div"
+            return f"<div>INVALID SYNTAX - Control is '{namespace}:{control_type}'</div>", "div"
         return builder_html  # type: ignore

src/taipy/gui/_renderers/_html/parser.py

@@ -93,7 +93,7 @@ def append_data(self, data: str) -> None:
     def parse_taipy_tag(self) -> None:
         tp_string, tp_element_name = self.taipy_tag.parse(self._gui)
         self.append_data(tp_string)
-        self.tag_mapping[f"taipy:{self.taipy_tag.control_type}"] = tp_element_name
+        self.tag_mapping[f"{self.taipy_tag.namespace}:{self.taipy_tag.control_type}"] = tp_element_name
         self.taipy_tag = None
 
     def get_jsx(self) -> str: