Steps to reproduce:

1. Go to Admin / Content structure.
2. Create new 'Landing page' content.
3. Being on block configuration page, click on 'Timeline' button.

Actual result:

See attachment.

After extending the "Timeline" functionality, the first element of the right menu is partially obscured.

Expected result:

Elements of right menu shouldn't be obscured by 'Timeline' functionality.

Comment:

Link to invision prototype: https://projects.invisionapp.com/d/main#/console/19075240/407712391/preview