Invariant Violation: Minified React error #31; visit http://facebook.github.io/react/docs/error-decoder.html?invariant=31&args[]=FetchError%3A%20invalid%20json%20response%20body%20at%20https%3A%2F%2Fwerkenbijactiefwerkt.nl%2Fapi%2Fpages%2Fonze-wereld%20reason%3A%20Unexpected%20token%20%3C%20in%20JSON%20at%20position%200&args[]= for the full message or use the non-minified dev environment for full errors and additional helpful warnings.