Story

The current Global Header plugin is configured using our legacy dynamic plugin system with `mountPoints`. As part of adopting Backstage’s New Frontend System, we need to migrate the Global Header plugin to use blueprints or create extensions wherever needed.

Background

Dependencies and Blockers

QE impacted work

Documentation impacted work

Acceptance Criteria

• Design the Blueprint first and get approval from the team
• UI components and translations are migrated to the New Frontend System model
• The existing `global.header/component`, `global.header/application-launcher`, `global.header/profile` & `global.header/help` mount points are replaced with new extensions implemented using NFS
• Migrate all existing header components configurations like priority, title, icon, etc., to `app.extensions` in the `app-config.yaml`. The header extension should define the configuration schema and correctly consume it to render the components
• Existing Global Header functionality must continue to work with no regression after the migration
• Should move the legacy app to app-legacy and the new app with NFS model should be in app
• The playwright script should run successfully on both legacy and NFS

Note: The `application/header` should be taken care of in a separate story involving the `application/provider` & `application/listener`

Refs:

NFS migration spike : https://docs.google.com/document/d/1Qb0T1Iu3ego50iO4V7NErSD44NdWSvk5n70pZvj-EmU/edit?tab=t.0#heading=h.zc5io9fn4km1

Backstage docs:
https://github.com/backstage/backstage/blob/master/docs/frontend-system/building-plugins/01-index.md

https://github.com/backstage/backstage/blob/master/docs/frontend-system/building-plugins/05-migrating.md