Hi Andreas,
Tricky problem.
I certainly don’t see an issue myself whether I navigate to the main events page/single events via existing links or even if I add/remove trailing slashes manually, it resolves without descending into a redirect loop.
If it’s a sporadic problem it’s going to be hard to get on top of – but it also sounds like something that, especially given your note about your customer experiencing greater difficulties when connecting via Citrix, is perhaps occurring at a level above anything we can control.
Just to confirm – it is only event pages that are being impacted upon?