Hi,
we've had a few bugs with urls in the past, and just a few days ago, our production server had one more. Please see the attached walkback. Please not that the walkback comes from VA Smalltalk, so it may read a little bit differently and the Sst classes are not present in Pharo.
There still are issues with decoding certain characters. I am not sure if this is still an issue in the latest Seaside version on Pharo, but here on VAST 8.6 I see this problem.
walkback.log