You can use Liner on Opera by installing Chrome extension on your Opera!
Installing 'Liner for Chrome' on Opera
To install Chrome extension on your Opera, please follow steps below:
1. Open Opera and install the “Open in Google Chrome” extension.
2. Go to the Chrome Web Store page for Liner and click 'Add to Opera' button.
3. Click Liner button on your top-right side of the screen.
Now also available for the Opera browser.