What's the recommended fix for the pollen filter seal?

[Hunders]

Hi guys.

I bought a B5.5 Passat a couple of weeks ago and after hearing about the leaking issues this car has I decided to go about solving the common problem areas after finding a little dampness under the carpet.

I started with the front sunroof drains by giving the nipples in the front doors a little pinch which got them flowing nicely and then I moved onto the plenum chamber which was in pretty good condition and didn't need much attention. The last thing on my list is the pollen filter seal but I'm unsure on what the generally recommended solution to this is?

Is it a case of running a bead of silicone/drain sealant down under the tray or getting some uprated seal from VW or elsewhere?

Cheers.