Opera Mail was once a part of the Opera browser, but has been removed from it. Now Opera Mail is available as a desktop email client that you can add to Windows, Linux or Mac OS. With Opera Mail you can open your email from Gmail, Yahoo, AOL, etc.
Open this page  on the Opera website to add the software to Windows. Alternatively, click Mac or Linux links on that page to add it to those platforms. Then run the Opera Mail installer.
When the software is running, you can add your email address and password from your webmail accounts. To add alternative accounts, click the Opera Mail button and select Mail Accounts. That opens the window below where you can press the Add button to open the account wizard.
Click Inbox to open your emails. Right-click an email to open a context menu with further options such as Reply, Forward and Delete. You can press a small arrow beside emails to expand a list of the replied to emails. Click an email once to open it on the right of the window as below. Alternatively, double-click to open an expanded email.
Press the Compose button to draft an email. There you can enter the email address in the To field. Click the paper clip icon to attach files. Press the Aa button to open the email’s formatting toolbar as below.
Opera Mail has the standard formatting options you would expect to find with most email text editors. You can select a variety of fonts and add bold, italic and underline formatting. You can also choose alternative text colors by pressing the Set Text Color button. Press the Unordered list button to add bullet points to emails. In addition, press the Superscript and Subscript buttons to add superscripts and subscripts to emails.
At the top right of the window there is a Default Mail Settings option. Press that button to open further options as below. There you can select three alternative mail layout options.
So with Opera Mail you can open your webmail without opening the account website. In addition, you can also import your emails from other clients such as Outlook Express. As Opera Mail has a variety of email options it’s a notable alternative.