Update #2: Check out this post too for an easier solution.

Update #1: This post is deprecated. That damned widget is not shown anymore.

Problem

I upgraded to the new look of Gmail but since then I always get a notification in the bottom right corner with “about the new look | send feedback”. Closing it doesn’t help, upon a new log in it’s there again.

Solution

Install Adblock Plus and add the following filter:

mail.google.com##div[class="GcwpPb-MEmzyf GcwpPb-bEO5kc"]

Something else

Does anybody know how to list the current filters in the new look? I can’t find it anywhere.