docstrings

Author: willmcgugan

src/textual/app.py

@@ -837,6 +837,7 @@ def __init_subclass__(cls, *args, **kwargs) -> None:
         return super().__init_subclass__(*args, **kwargs)
 
     def _get_dom_base(self) -> DOMNode:
+        """When querying from the app, we want to query the default screen."""
         return self.default_screen
 
     def validate_title(self, title: Any) -> str:

src/textual/dom.py

@@ -238,6 +238,9 @@ def __init__(
     def _get_dom_base(self) -> DOMNode:
         """Get the DOM base node (typically self).
 
+        All DOM queries on this node will use the return value as the root node.
+        This method allows the App to query the default screen, and not the active screen.
+
         Returns:
             DOMNode.
         """