New label button disappears when only prioritized labels

Summary

The "New label" button disappears when all labels are marked as "Prioritized label"

Steps to reproduce

If label list is empty:

  1. Create a label
  2. Set label as Prioritized label
  3. Refresh page
  4. New label button is gone

alternative

  1. Create multiple labels
  2. Set all but one label to prioritized label
  3. Refresh page
  4. Set last label to Prioritized label
  5. New label button is gone

What is the current bug behavior?

The "New label" button disappears, when there are ONLY prioritized labels in a project.

What is the expected correct behavior?

The "New label" button should be visible

Relevant logs and/or screenshots

gitlab-new-label-prio

Output of checks

This bug happens on GitLab.com