HAR File Results in Firefox is different from LoadRunner Controller result using HTTP runs.

Hi All

Good Day

I ran a performance test in HP LoadRunner and the response time results in the HAR file generated in Mozilla Firefox is much different from the result in the HP LoadRunner Controller. It is just a login funciton. 

May I know what are the reasons why these are happening? Why is the response time result in HP LoadRunner Controller's result much different from the HAR file in Mozilla Firefox? 

What should I look in Mozilla Firefox's HAR file to be able to validate the results if they are correct and would have the same result in HP Loadrunner's Controller? What data in the HAR file's response time should be included in the measurement of the response time