Starting WebSpellChecker version 5.28.4.0, the following symbols are not allowed to be used in the words for adding them to the Custom User Dictionary via WProofreader UI (in the Dictionary tab):
,s,xA0 ,"^$*+?=!:÷`,,|,/,(,),[,],{,},>,<,@,%,&,#,;,_,~,u061F,u060C,u061B,u0001-,u001F,u0080-,u00B6,u00B8-,u00BF,u2000-,u200A,u200C-,u2018,u201A-,u266F,u2E00-,u2E7F
