Pick broadcast message colors from palette instead of hex color codes
Description
Back in 8.10.6, broadcast message background and font colors could be picked from a color palette. Today, users have to manually enter the color hex codes, which is unintuitive.
Proposal
Allow users to pick the colors they want from a color palette again.
Links / references
This was mentioned by an EE customer in https://gitlab.zendesk.com/agent/tickets/57659