The PDF reader may be included in Firefox within three months, said Andreas Gal, a Mozilla researcher who on Wednesday unveiled work the company had done quietly for the last month.

If Mozilla follows through on its plans, it would make Firefox the second major browser -- after -- to offer in-browser PDF rendering.

But while Chrome relies on an API (application programming interface) to craft its own native-code plug-in, Mozilla will exclusively use HTML5 and JavaScript to display Adobe's popular document format.

Gal touted that as more secure.

"The traditional approach to rendering PDFs in a browser is to use a native-code plug-in, either Adobe's own PDF Reader or other commercial renderers, or some open-source alternative," Gal said in a post to his .