Features

Read Later saves the active tab to Instapaper.
Read Later and Close Tab quickly puts tabs aside for later reading.
Read Now saves and opens the tab in Instapaper right away.
Open Reading List gives you quick access to your Instapaper reading list.

Keyboard modifiers

Hold the Alt key and click Read Now to open an Instapaper-formatted view of the current tab without saving it to your reading list.
Hold the Shift key and click Read Now to open a copy of the tab with Instapaper.
Hold the Shift key and click Open Reading List to force-open it in a new tab.

Comparison to the official extension The official Instapaper for Firefox only allows you to save web pages for later, whereas Read with Instapaper gives you more reading options and a quick way to open your reading list. The official extension slows down your average web performance by loading extra JavaScript onto every web page you visit. Read with Instapaper doesn’t do this unless you specifically choose to read a page with Instapaper. Requires a free Instapaper.com account.