Treats the #var and #varexists parser functions as volatile to prevent unexpected behaviour due to template caching. Disabling this reinstates the legacy behaviour.
Allows to define an array of functions which should not be available within the wiki. Omit any # while adding functions.
For example: $egVariablesDisabledFunctions = [ 'var_final', 'vardefineecho' ]; // to disable '#var_final' and '#vardefineecho' functions