Hey @indiabhi I have been working on this bug in #1803 . For this pr although preview button is suppose to be changed at multiple locations :)
Also, if you look at the issue carefully, a label saying previewing comment must also appear before the button. Go ahead and add it :)
previewing comment
This is a duplicate of #1803 so let's close this one.
Thanks for working on it though @indiabhi :)
Pull-Request has been closed by pingou