Added WCF.PageVisibilityHandler
Added WCF.PageVisibilityHandler

MenesesEvandro/WCF,SoftCreatR/WCF,0xLeon/WCF,NBZ4live/WCF,Cyperghost/WCF,WoltLab/WCF,MeinAccount/WCF,joshuaruesweg/WCF,Morik/WCF,joshuaruesweg/WCF,joshuaruesweg/WCF,MeinAccount/WCF,cashcat/WCF-1,WoltLab/WCF,SoftCreatR/WCF,0xLeon/WCF,Cyperghost/WCF,Cyperghost/WCF,WoltLab/WCF,ramiusGitHub/WCF,SoftCreatR/WCF,Morik/WCF,MenesesEvandro/WCF,NBZ4live/WCF,SoftCreatR/WCF,Cyperghost/WCF,Morik/WCF,Cyperghost/WCF,ramiusGitHub/WCF,cashcat/WCF-1,PhrozenByte/WCF2,0xLeon/WCF,PhrozenByte/WCF2,WoltLab/WCF,Morik/WCF