diff --git a/dotnet/src/webdriver/Firefox/FirefoxDriver.cs b/dotnet/src/webdriver/Firefox/FirefoxDriver.cs
index 99f9cb3ea68c6..123f0eb6dc545 100644
--- a/dotnet/src/webdriver/Firefox/FirefoxDriver.cs
+++ b/dotnet/src/webdriver/Firefox/FirefoxDriver.cs
@@ -393,6 +393,7 @@ public Screenshot GetFullPageScreenshot()
         /// Creates a session to communicate with a browser using the Chromium Developer Tools debugging protocol.
         /// </summary>
         /// <returns>The active session to use to communicate with the Chromium Developer Tools debugging protocol.</returns>
+        [Obsolete("CDP support for Firefox is deprecated and will be removed in future versions. Please switch to WebDriver BiDi.")]
         public DevToolsSession GetDevToolsSession()
         {
             return GetDevToolsSession(new DevToolsOptions() { ProtocolVersion = FirefoxDevToolsProtocolVersion });
diff --git a/dotnet/src/webdriver/Remote/RemoteWebDriver.cs b/dotnet/src/webdriver/Remote/RemoteWebDriver.cs
index 8483eb2fbc3ec..0950c84949ff9 100644
--- a/dotnet/src/webdriver/Remote/RemoteWebDriver.cs
+++ b/dotnet/src/webdriver/Remote/RemoteWebDriver.cs
@@ -428,7 +428,7 @@ public ReadOnlyCollection<IWebElement> FindElementsByCssSelector(string cssSelec
         /// <returns>The active session to use to communicate with the Developer Tools debugging protocol.</returns>
         public DevToolsSession GetDevToolsSession()
         {
-            if (this.Capabilities.GetCapability(CapabilityType.BrowserName) == "firefox")
+            if (this.Capabilities.GetCapability(CapabilityType.BrowserName) is "firefox")
             {
                 if (_logger.IsEnabled(LogEventLevel.Warn))
                 {