Preview App and Its Highlighting BUGS
BUG In PREVIEW HIGHLIGHT FUNCTION
When highlight is active and you are studying and making highlights, if you happen to hit shift A (select all), it will highlight everything in the document, which is irreversible even with an undo right afterwards. INSANITY. This destroys all previous highlights in the document. Furthermore, the only corrective is to open the Inspector and highlight everything and delete It all, thus returning the document back to white, meaning no highlights. TOTAL INSANITY.