> I'm not so sure about that anymore.

Simpl(-istic) example, imagine a data-structure

%unicode = ( ..., "BOM" => "\x{FEFF}", ... )

and transfer it as JSON.

Removing all "\x{FEFF}" would wreck the data.

While a BOM at the strings start is illegal JSON, it's not uncommon.

So removing just a leading BOM, before trying to convert the JSON, is safe.