Netexport is not working for Firefox new version 49

[satishgowda]

I was working with Firefox 47 version with "netExport-0.9b7.xpi" and firebug version "firebug-2.0.17-fx.xpi" it was working fine to capture network traffic into HAR file
now with new version 49 i am using "netExport-0.9b7.xpi" and firebug version "firebug-2.0.18-fx.xpi" it is not working fine

could you please check on this

i referred https://eveningsamurai.wordpress.com/2013/06/29/capturing-network-traffic-using-selenium-webdriverfirebug/