I received a pdf from a client containing several invoices. Upon further inspecting, some lines on the invoice seem digitally produced. When I tried selecting the page, copying it then pasting it on paint, the lines that seemed suspicious disappeared.
I should note that the source invoice paper are very thin. So before jumping to any conclusions, is it common that some printers or printing software compensate for blurry or lost lines and text and try to “enhance them”?