lib/firebug/session.rb in firebug-0.1.9 vs lib/firebug/session.rb in firebug-0.1.10

@@ -19,10 +19,10 @@
 
     # @param [String] value
     def user_agent=(value)
       # Pyro seems to truncate the value and since it also uses this value when finding the session, it's important
       # we do the same.
-      super(Firebug.configuration.truncate_user_agent ? value[0...120] : value)
+      super(Firebug.configuration.truncate_user_agent ? value&.slice(0...120) : value)
     end
 
     # @return [String]
     def cookie_data
       data = { session_id: session_id, ip_address: ip_address, user_agent: user_agent, last_activity: last_activity }