Some of my colleagues have been hesitant to make the switch from their desktop email apps (e.g., Outlook) to the Gmail Web interface because they don't want to lose the email "preview pane." ["Preview pane" is a misnomer, actually, since one can read an entire email message and respond to it from that screen, so it should probably be called "view pane"]. But thanks to Peter B and Michael K, there is a Google Lab that allows you to toggle on/off a preview pane. The lab is called "Preview Pane" and it's actually been around since about 2011 (more info).
To enable the lab, follow these steps:
- Click the settings button (a.k.a., the "gear" button) in the top right corner of the Gmail Web app.
- Choose "Settings."
- On the settings page, click the "Labs" link located at the top of the settings page, toward the right side of the links.
- If you don't see "Preview Pane" by Peter B & Michael K listed in your laps, you can search for it using the search box.
- Click the "Enable" radio button to enable the lab.
- Scroll to the bottom of the page and click the "Save Changes" button.
Gmail should reload and you will be alerted to a toggle button that has been added just left of the settings/gear button on the Gmail page. Clicking that button will toggle the preview pane on and off.