HBBTV on Xtrend 4000 (OpenPLI 4.0)

Hi !

I reflashed my xtrend 4000 today using latest openpli 4.0 and installed the enigma2-plugin-extensions-et-webbrowser - 1.6.1-r0 plugin as suggested on other sites. I then rebooted and pressed the red button on channels showing HBBTV support but nothing happens.
What do I miss here to get HBBTV running ?