PURPOSE
Improve and make color management coherent in event models. Notably consider
colorless tags as being used for internal management only, and not displayed
in frontend.
SPECIFICATIONS
Ensure tags without color are not displayed in frontend for both event and
track models (event main page, track display, agenda). Also ensure a default
random color is given when creating tags so that they are displayed by
default.
When a category used as a dropdown menu has no tags to display hide it in
order to have void categories in filtering section.
LINKS
Related to testing of EventOnline
Task ID-2314778
Fwd port of PR #55625
PR #55642
Thibault Delavallée
58b0fb2da1