A new feature to Zotero 6 is the ability to take notes in a pdf using the Zotero reader. While in Zotero, double-click to open the document.
The buttons, in order, are:
In practice, the highlighting may not always work due to the formatting of the pdf. If the pdf was born digital or was scanned from print using OCR, then highlighting should work.
Notes look like sticky notes on the page, but only show the note when clicked. These notes may be imported into Zotero’s Notes tab connected to the citation.
“Select area” encloses an area in a box.
You may pick from five colors for the highlighting, notes, and lines.