Fails to compile on Particle.io WebIDE

Error on WebIDE is
lib/ArduinoJson/ArduinoJson/Strings/SizedFlashStringAdapter.hpp:19:69: 'strncmp_P' was not declared in this scope

Particle.io WebIDE target device Gen3 Mesh (Argon or Xenon)
Library version ArduinoJson (6.11.4)

Reproduce
Open WebIDE
Select libraries, Search ArduinoJSON, select JsonParserExample.ino then select USE THIS EXAMPLE
Compile the App and error is produced