[MC-83923] Worlds converted from 1.8.x cause JSON error with signs, etc.

When you convert an 1.8.x or earlier world to 15w31a or 15w31b, you disconnect with JSON error every time you approach a sign etc. or with a message telling you to set JSON parsing to lenient.

Environment

Java 1.8, Windows 7 Ultimate x64 Portuguese (Portugal)

Linked issues

duplicates 1

MC-82968 Kicked from server when in certain area: com.google.gson.stream.MalformedJsonException: Use JsonReader.setLenient(true) to accept malformed JSON at line 1 column 1 Resolved

Comments 2

migrated 2015-07-30T15:53:16Z

Got the same issue and can confirm it.

In singeplayer everything works fine, all the Signs are loading.
As soon as I put the world onto a 15w31b Server, it won't let me in.

migrated 2015-07-30T16:18:14Z

Thank you for your report.
However, your ticket has been resolved as a duplicate.

This issue has been linked to the original bugreport: MC-82968. You can find or add further information on that report.
Please search before reporting any bugs, as it's likely that one exists already.