This issue occurs with the Boost theme and the blocks drawer.

When editing a certificate template, it's not possible to show/hide the blocks drawer. Clicking the toggle icon causes a JS error : 

Error: cannot call methods on tooltip prior to initialization; attempted to call method 'hide'

It might be a conflict between Jqueryui (use for the draggable in the template edit page) and Boostrap.

How to reproduce : 

• Boost theme and the blocks drawer need to be enabled
• Go to a template editing page (Certificates -> Manage certificate templates -> chose any certificate)
• Try showing/hiding the blocks drawer

A similar issue has already been reported on some others Moodle page : https://tracker.moodle.org/browse/MDL-74459