(Mr. Savard sincere thanks for your update fixing the YMail Contacts issue.) Excellent extension as usual by the excellent developer!

I've tried multiple ad blockers to remove all the annoying ads in Yahoo Mail, and this is the only one that removes all of them. And every time Yahoo makes a change that causes the ads to reappear, the Developer quickly issues an update to the extension that removes the ads again. And he's very responsive to questions and comments!
And the Chrome version works as well.

在国内能下载诶

i f*cking love you.

супер! работает отлично

Very useful addon

It's working with blocking ads on Yahoo Mail now. Jason has fixed it for Yahoo Mail. Thank you Jason. Really appreciate it!

Used to be great, but it has now stopped working. Viewable area is no longer expanded to the right hand side.

Unfortunately, no longer works for Yahoo mail