Automattic/jetpack — pull request #1366 by jeherve (2014-12-04 11:30:39+00:00)
Title: Facebook Like Box Widget: add filter to title

The `jetpack_facebook_likebox_title` filter will allow site owners to remove the link in the widget title, or have it open in a new window.

Fixes #892

Suggested here:
https://wordpress.org/support/topic/filter-on-facebook-widget-title?replies=1