diff --git a/src/textual/_context.py b/src/textual/_context.py
index d28a1b15a2..039bb7b4ef 100644
--- a/src/textual/_context.py
+++ b/src/textual/_context.py
@@ -1,7 +1,7 @@
 from __future__ import annotations
 
 from contextvars import ContextVar
-from typing import TYPE_CHECKING, Any, Callable, TypeVar
+from typing import TYPE_CHECKING, Any, Callable
 
 if TYPE_CHECKING:
     from .app import App
@@ -14,10 +14,6 @@ class NoActiveAppError(RuntimeError):
     """Runtime error raised if we try to retrieve the active app when there is none."""
 
 
-ContextVarType = TypeVar("ContextVarType")
-DefaultType = TypeVar("DefaultType")
-
-
 active_app: ContextVar["App[Any]"] = ContextVar("active_app")
 active_message_pump: ContextVar["MessagePump"] = ContextVar("active_message_pump")
 
diff --git a/src/textual/app.py b/src/textual/app.py
index ba0e79bb9f..e01f6842cf 100644
--- a/src/textual/app.py
+++ b/src/textual/app.py
@@ -2687,6 +2687,7 @@ def _build_driver(
         return driver
 
     async def _init_devtools(self):
+        """Initialize developer tools."""
         if self.devtools is not None:
             from textual_dev.client import DevtoolsConnectionError
 
@@ -2707,6 +2708,11 @@ async def _process_messages(
         message_hook: Callable[[Message], None] | None = None,
     ) -> None:
         async def app_prelude() -> bool:
+            """Work required before running the app.
+
+            Returns:
+                `True` if the app should continue, or `False` if there was a problem starting.
+            """
             await self._init_devtools()
             self.log.system("---")
             self.log.system(loop=asyncio.get_running_loop())
diff --git a/src/textual/css/styles.py b/src/textual/css/styles.py
index 27dc9f6892..8fe230bc75 100644
--- a/src/textual/css/styles.py
+++ b/src/textual/css/styles.py
@@ -554,7 +554,6 @@ def is_animatable(cls, rule: str) -> bool:
         return rule in cls.ANIMATABLE
 
     @classmethod
-    # @lru_cache(maxsize=1024)
     def parse(
         cls, css: str, read_from: CSSLocation, *, node: DOMNode | None = None
     ) -> Styles: