[rb] add error messages for when devtools is not supported

Author: titusfortner

rb/lib/selenium/webdriver/firefox/driver.rb

@@ -42,6 +42,10 @@ def browser
         private
 
         def devtools_url
+          if capabilities['moz:debuggerAddress'].nil?
+            raise(Error::WebDriverError, "DevTools is not supported by this version of Firefox; use v85 or higher")
+          end
+
           uri = URI("http://#{capabilities['moz:debuggerAddress']}")
           response = Net::HTTP.get(uri.hostname, '/json/version', uri.port)
 

rb/lib/selenium/webdriver/remote/driver.rb

@@ -52,7 +52,8 @@ def devtools_url
         end
 
         def devtools_version
-          capabilities['se:cdpVersion'].split('.').first
+          capabilities['se:cdpVersion']&.split('.')&.first ||
+            raise(Error::WebDriverError, "DevTools is not supported by the Remote Server")
         end
       end # Driver
     end # Remote