Issue with ~disconnectonclose

Hi Everyone

We have a couple of WEBGUI/ ITS transactions active which our users work with. Of course non of them use "System / Close" to exit the transaction but just close the browser window. This works fine with Internet Explorer and the parameter ~disconnectonclose where the session and active enqueues are removed. But with Firefox and Chrome the session is NOT closed and the enqueued entries remain locked.

Can anyone tell me why this does not work on Chrome / Firefox but only with IEX and also if there is a work around so that our users can work with their preferred browser? We are on kernel release 721 / Patchlevel 211 and SAP_BASIS SAPKB73104

Thanks for any input

Harry