[Seaside] How to get the value of a javascript variable?

[Michel Bany]

> Hi. Last week I've sent to this list (and to Michel separately) an  
> e-mail with two attachments containing an example with the code of  
> this problem. Neither has appeared in the mailing list nor haven't  
> reply from Michel.
>

Here is another attempt.
ftp://ftp.bany.fr/seaside/GetBrowserInfo-mb.2.mcz

This is not the best possible solution, however I must confess that I  
do not know how to fire a Seaside callback from a javascript before  
any rendering occurs.

HTH
Michel.