fix reading being blanked when focused (#605)
fix reading being blanked when focused (#605)

LucasCabello/anki,kenjhim/anki,holycrepe/anki,florianjacob/anki,weihautin/anki,subfusc/anki,abeyer/anki,weihautin/anki,jkitching/anki,go38/anki,hssm/anki,jakesyl/ruby-card,eduOS/anki,Arthaey/anki,sunclx/anki,ospalh/libanki3,Stvad/anki,jakesyl/ruby-card,socialpercon/anki-1,hssm/anki,xuewenfei/anki