In the example JSON two-character escape sequence on https://plantuml.com/json
@startjson
{
"reverse solidus character (U+005C)": ["\\\\", "a\\b"]
}
@endjson
displays as:
But I would have expected the top box to be "\\" not just "\".
Edit: Also - see Th's note below with similar issues for \\n, \\r, \\t.
PS The full example also has a typo "beetwen"