R1:0bffb8cd211b

Fix notification hover, maybe

Summary: Not sure how to test this, but assume it's coming from this hover.

Test Plan: n/a

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T3425

Differential Revision: https://secure.phabricator.com/D6255