When I checked other people’s issues in some repositories, I found something that might be wrong.
example1：Migrate SearchByIdModal to new scss color theme · Issue #2737 · kids-first/kf-portal-ui · GitHub
In the timeline of Issue, it shows that the programmer added a label, but there is no label in the right navigation bar.
example2: [cygnus][doc] Add a note about IPv6 support · Issue #1058 · telefonicaid/fiware-cygnus · GitHub
Contrast to example 1, it shows some label right navigation bar, but there is no label “add label”events in this issues timeline.