• Make a movie for Hidamari #1158 Make a movie for Hidamari
• ChairLift: Add Brewfile bundles for Wallpaper Slideshow and Video Wallpaper #1159 ChairLift: Add Brewfile bundles for Wallpaper Slideshow and Video Wallpaper
• Damask: Ship Flatpak sandbox overrides and systemd user background service #1160 Damask: Ship Flatpak sandbox overrides and systemd user background service
• Damask: First-run configuration hook and non-destructive activation #1161 Damask: First-run configuration hook and non-destructive activation

created_date: "2026-09-24"
document_status: draft
closed_date: null

Feature: 20260924190738-4b676228-common-wallpaper-experiences

Overview

Bluefin users can opt into slideshow and looping-video wallpaper experiences through ChairLift bundles while retaining the desktop’s native timed wallpaper behavior until they choose rotation. Four existing sub-issues own artwork, bundle surfacing, Damask integration and first-run configuration. Source: common#1157.

Requirements

• Offer two optional bundles
  People can install Wallpaper Slideshow (Damask) and Video Wallpaper (Hidamari) from ChairLift without installing both.
• Make Damask access safe
  The slideshow can read only packaged and user wallpaper folders and runs its background service only when installed.
• Preserve native wallpaper defaults
  First use seeds a 24-hour slideshow interval but leaves active-source none until the user opts in.
• Ship a working video sample
  Hidamari includes one project-owned looping movie selectable through the optional video bundle.
• Explain platform limitations
  Users learn when XWayland fullscreen pausing or NVIDIA Wayland decoding is unsupported before relying on it.

Constraints

• Bundles belong to /usr/share/ublue-os/homebrew and to ChairLift’s brew_bundles_group; no forced wallpaper replacement or automatic uninstall path.
• Damask sandbox access is read-only for /usr/share/backgrounds and xdg-data/backgrounds; systemd user service must avoid failed restart loops when absent.
• Video playback on XWayland/Wayland must report real limits rather than promising fullscreen pause or GPU decode.

Acceptance Criteria

• Offer two optional bundles
  Both Brewfile bundles appear as distinct Install actions; removing them uses ChairLift Flatpak management.
• Make Damask access safe
  The Flatpak has read-only wallpaper folder access and damask.service remains inactive when Damask is absent.
• Preserve native wallpaper defaults
  On a fresh session GNOME day/night wallpaper remains unchanged until rotation is explicitly enabled.
• Ship a working video sample
  The movie is packaged, can loop in Hidamari and does not start playback without user choice.
• Explain platform limitations
  Documentation states X11-dependent pause behavior, software decode fallback and Damask timer reset on relogin.

Technical Approach

• Work map: Make a movie for Hidamari #1158 movie, ChairLift: Add Brewfile bundles for Wallpaper Slideshow and Video Wallpaper #1159 bundles, Damask: Ship Flatpak sandbox overrides and systemd user background service #1160 sandbox and user service, Damask: First-run configuration hook and non-destructive activation #1161 non-destructive first-run hook. Keep those four links intact.
• The current source proposal uses ConditionPathExists=| for the user service, interval 86400 and active-source=none; verify those exact interactions when designing the implementation.

Success Metrics

• Neither wallpaper engine runs before selection; both can be installed from the ordinary UI and the stock day/night cycle remains intact.

Non-Goals

• Do not build a second wallpaper manager inside ChairLift or replace desktop wallpaper settings.

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