It looks like FME is very flexible in reading JSON files containing smaller errors. In our case we detected an extra "," at the end of an array. The JSONValidator detects this error clearly with the following error message: 'A trailing comma was found after the last value in an object or array'. But the JSON-Reader never validates JSON files and seems to be flexible and okay with minor issues like the one occured here. Please improve the JSON reader to validate the content of a file by option.
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