To set up Yahoo Mail to open emails and search results in tabs:
How to Open Multiple Emails Side by Side in Yahoo Mail
To open multiple messages side by side in Yahoo Mail tabs:
Make sure Tabs are enabled for multitasking (see above). With the Yahoo Mail preview pane closed, click each message to open it in a separate tab. With the preview pane enabled, double-click the desired message. Alternatively, click the message once and press Enter.
How to Turn on Tabs for Multitasking in Yahoo Mail
Hover the mouse cursor over the gear icon in the Yahoo Mail toolbar. Select Settings from the menu that shows. Open the Viewing email category. Make sure Tabs is selected under Multitasking. Select Save.
