[umangd]

just found out that gmail has retired the lab feature, along with many others. That's really sad. http://gmailblog.blogspot.in/2012/05/say-hello-or-ola-or-hal...

[epikur]

There appears to be a number of chrome extensions that support gestures, so perhaps you can find or configure one that works similarly ("Pig Toolbox," for example). Or learn the Gmail keyboard shortcuts.