Spurious 500 errors with localhost endpoint

[LaurensRietveld]

I'm using YASGUI to query my own application, running on localhost.
It seems that on the first time I query a dataset, Yasgui tries to query it through its own server, which makes no sense with localhost... Indeed, on that first attempt, I get a 500 error. On all subsequent attempts, YASGUI queries my server directly and everything works fine.

Note that this could be considered an acceptable annoyance (it only happens on the first attempt). But in my application, every resource acts as a SPARQL endpoint, so I get this annoying behaviour each time a query a new resource :-(

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