Migrate to the new Preferences System

🎯The objective

The aim of this project is to support mobile foundations by modernizing the preferences system. This allows us to better react to preferences changes, and provides a modern look and feel to the preferences.

🎒Resources

• https://github.com/thunderbird/thunderbird-android/pull/8985

🦮Rules of the Road

ℹ️ Initial definition of requirements and limitations, the scope of this feature and other potential considerations in order to keep the project narrow and focused.

🟢In Scope

• Extend the new preferences system to support all missing control types (e.g. Switches)
• Extend from just the ability to add account-related preferences to all general preferences
• Migrate away from the old preferences system
• Clean up after old preferences system and remove code

🔴Out of Scope

• Revise which preferences we want to keep or remove

Cross-Functional Tasks

⁉️QA

• Do a manual QA run to confirm that all migrated preferences continue to function and have their intended effect.

🤝Support - Product

• Update SUMO screenshots