I want to remove some sensitive info from a pdf before emailing it. So I removed some info from a pdf file by colouring white over the text then printing to pdf. When opening new pdf document with edge or chrome the info is removed however with firefox the info briefly appears before disappearing again. So somehow after whiting out the text and printing to a new pdf file the info is somehow still there??? I would have thought by printing to a new file the new pdf would not hold the text underneath and print "white" blank space... no data behind it, am I incorrect in assuming so?