Gmail – Tab with Gmail account spontaneously switches to primary email

Yahoo - @Mehper has it right about Yahoo - left-clicking will open the mail in a new tab. Just click back over to the Inbox tab to see the full list again. This gives you tab functionality, just not at the browser level.

An alternative to doing this is to change your "mail options" to show the email preview pane in your inbox view. To see this you can go to the top left (next to your profile avatar) and select:

Options > Mail Options > In a scrolling list (show preview pane) (under behavior)

This will allow you to open email at the bottom with the inbox on the top (no there is no way to make the split vertical)

Outlook - I don't know how to do this in Outlook.

Gmail - For Gmail, you can try using basic HTML view if you want the middle-click functionality: https://mail.google.com/mail/?ui=html&zy=h

This is a basic view that allows you to middle click to open email in new tabs.

For more about this go to this link: http://support.google.com/mail/bin/answer.py?hl=en&answer=15049

NOTE: The basic HTML view is a little different from what you're used to because the following features aren't available:

• Chat
• Spell checker
• Keyboard shortcuts
• Ability to manage filters
• Adding, editing, importing, or deleting contacts
• Custom 'From:' addresses
• Rich formatting

The shortcut that does exactly what is asked for here is 'u', which Google labels "return to thread list," which is what it does if you're in a conversation view (i.e. a single email thread). However, if you're already looking at a list of threads (e.g. your inbox), 'u' will refresh that list.

Unlike "g, i", 'u' works to refresh any thread list you're looking at, and also does not move the cursor back to the top.

Like "g, i", the 'u' shortcut is part of the set of keyboard shortcuts that might be disabled. If that's the case, you can enable them by setting "Keyboard shortcuts on" in Gmail settings, under the "General" tab. You can also do it by pressing the '?' key in the thread or conversation view, which brings up a list of keyboard shortcuts and their meanings (although, as demonstrated here, those meanings aren't always clear). There's a link in the middle of the box allowing you to toggle whether the extended keyboard shortcuts are enabled or disabled: