[nobody7290]

If you upgrade your device, the Browser history and cookies are lost.
This is annoying, since, if you use web-forums which authenticate you with a cookie, you have to enter your passwords again.

Does anyone knows a workaround ?

[mckinneycm]

No workaround. When you upgrade, the process wipes the device before installing the new OS. Since History and Cookies are considered temporary files, there is no way to back them up and then restore them.

[nobody7290]

Thanks - at least I now know that I did not miss anything important.

Besides that, I think it would be a good thing to include the cookies in the automatic wireless backup. This is not much data.
The wireless backup restores even icon posititions on the Screen, so why not include the cookies.