diff --git a/py/selenium/webdriver/common/bidi/storage.py b/py/selenium/webdriver/common/bidi/storage.py
index 620477aeae6da..4404baca7a66a 100644
--- a/py/selenium/webdriver/common/bidi/storage.py
+++ b/py/selenium/webdriver/common/bidi/storage.py
@@ -15,7 +15,7 @@
 # specific language governing permissions and limitations
 # under the License.
 
-from typing import Optional, Union
+from typing import Any, Optional, Union
 
 from selenium.webdriver.common.bidi.common import command_builder
 
@@ -85,12 +85,19 @@ def from_dict(cls, data: dict) -> "Cookie":
         -------
             Cookie: A new instance of Cookie.
         """
-        value = BytesValue(data.get("value", {}).get("type"), data.get("value", {}).get("value"))
+        # Validation for empty strings
+        name = data.get("name")
+        if not name:
+            raise ValueError("name is required and cannot be empty")
+        domain = data.get("domain")
+        if not domain:
+            raise ValueError("domain is required and cannot be empty")
 
+        value = BytesValue(data.get("value", {}).get("type"), data.get("value", {}).get("value"))
         return cls(
-            name=data.get("name"),
+            name=str(name),
             value=value,
-            domain=data.get("domain"),
+            domain=str(domain),
             path=data.get("path"),
             size=data.get("size"),
             http_only=data.get("httpOnly"),
@@ -125,14 +132,14 @@ def __init__(
         self.same_site = same_site
         self.expiry = expiry
 
-    def to_dict(self) -> dict:
+    def to_dict(self) -> dict[str, Any]:
         """Converts the CookieFilter to a dictionary.
 
         Returns:
         -------
             Dict: A dictionary representation of the CookieFilter.
         """
-        result = {}
+        result: dict[str, Any] = {}
         if self.name is not None:
             result["name"] = self.name
         if self.value is not None:
@@ -242,14 +249,14 @@ def __init__(
         self.same_site = same_site
         self.expiry = expiry
 
-    def to_dict(self) -> dict:
+    def to_dict(self) -> dict[str, Any]:
         """Converts the PartialCookie to a dictionary.
 
         Returns:
         -------
             Dict: A dictionary representation of the PartialCookie.
         """
-        result = {
+        result: dict[str, Any] = {
             "name": self.name,
             "value": self.value.to_dict(),
             "domain": self.domain,
diff --git a/py/selenium/webdriver/common/options.py b/py/selenium/webdriver/common/options.py
index 67e5765645133..fc76c6fd832fc 100644
--- a/py/selenium/webdriver/common/options.py
+++ b/py/selenium/webdriver/common/options.py
@@ -422,7 +422,7 @@ def __init__(self) -> None:
         self._caps = self.default_capabilities
         self._proxy = None
         self.set_capability("pageLoadStrategy", PageLoadStrategy.normal)
-        self.mobile_options = None
+        self.mobile_options: Optional[dict[str, str]] = None
         self._ignore_local_proxy = False
 
     @property
diff --git a/py/selenium/webdriver/common/virtual_authenticator.py b/py/selenium/webdriver/common/virtual_authenticator.py
index a434de83741df..19b0ec615e7c5 100644
--- a/py/selenium/webdriver/common/virtual_authenticator.py
+++ b/py/selenium/webdriver/common/virtual_authenticator.py
@@ -24,17 +24,17 @@
 class Protocol(str, Enum):
     """Protocol to communicate with the authenticator."""
 
-    CTAP2: str = "ctap2"
-    U2F: str = "ctap1/u2f"
+    CTAP2 = "ctap2"
+    U2F = "ctap1/u2f"
 
 
 class Transport(str, Enum):
     """Transport method to communicate with the authenticator."""
 
-    BLE: str = "ble"
-    USB: str = "usb"
-    NFC: str = "nfc"
-    INTERNAL: str = "internal"
+    BLE = "ble"
+    USB = "usb"
+    NFC = "nfc"
+    INTERNAL = "internal"
 
 
 class VirtualAuthenticatorOptions: