Inconsistent label colors on issue and issue details sidebar

Summary

Label color on issue details sidebar doesn't correspond with that of label under issue description after label color gets changed.

Steps to reproduce

1. Create label for project level
2. Attach label to an issue
3. Update label color

What is the current bug behavior?

Changing label color updates the label color on issue details sidebar but not on issue description.

What is the expected correct behavior?

Changing label color should update the color for both issue description and issue details sidebar.

Relevant logs and/or screenshots

Issue description

Issue details sidebar

Google analytics label color doesn't correspond with the one in the issue details sidebar.

Output of checks

This bug happens on GitLab.com.