Menu toggle key does not work in WiB

I set up a key like Alt+F10, it works from the TelnetCE main menu, but as soon a the session connects (WEB) the toggle key does not work anymore. And then I can't go back to the main menu. Is this a known issue?

Using Intermec CK3X and TelnetCE 7.3.234.

Thanks for your help,

Fred.