Bug - anchor to null on hover over the responses buttons (before beginning an exercise)

Summary:
Steps to follow to replicate the bug:

1. open Minuet
2. open an exercise
3. before pressing "New Question", hover over the responses ("your choises") buttons
4. in the console, two "null" error will appear

link on Youtube

Reviewers: sandroandrade

Subscribers: stefant

Tags: Minuet

Differential Revision: https://phabricator.kde.org/D4326