[Users] One filter not working

[Neil]

I have a total of 11 filters set up. Ten of them are working. The
eleventh  is set up to deal with the bug report emails I get. I decided
to put them into a separate folder.

So I created the folder to hold those emails and set up the filter. It
checks that 

To contains "thewildbeast"

 and then is supposed to move those emails to the relevant folder.
 Nothing happens. The emails are not moved.

Out of interest I set up a similar filter in TBird (I use IMAP so all
emails are available) and there it works with no problem.

Other filters that I have set up in claws also check for 'To
contains ...' and they work. 

Any ideas anyone please?

Neil