The document discusses the stabilization of Chromium's Wayland support, detailing its architecture, history, and current status as of June 3, 2024. It outlines relevant code areas, the timeline of Ozone/Wayland development from its inception in 2013 to ongoing experimental features, including challenges that need to be addressed for stabilization. Key stabilization blockers include drag and drop functionality, tab dragging, and scaling issues.

1. Stabilizing Chromium’s
Wayland support
and
2024-06-03 @ Web Engines Hackfest 2024
Antonio Gomes Max Ihlenfeldt
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2. Agenda
1. Relevant Chromium architecture
2. History of ozone/wayland
3. Current status
4. Moving towards stabilization
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3. Relevant Chromium
architecture
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4. Relevant code areas
//chrome/browser - high-level browser code
//ui/views - "Views" desktop UI toolkit
//ui/aura - windowing and event abstraction
//ui/ozone - platform abstraction
//ui/platform_window - platform abstraction
glue
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5. Ozone
platform abstraction layer handling low level input
and graphics
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6. History of ozone/wayland
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7. Timeline
2013: Debut of Ozone, Crosswalk, and Intel's
downstream ozone/wayland
WebRuntime that ran natively on Wayland-based
systems
Good community adoption
2014-2015: Tizen EFL
2015: Entered maintenance mode circa m49
2016:
Goal: testing proposes of Ash/Chrome on linux
desktop
first upstream ozone/wayland commit
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9. Timeline
Mus+Ash
New built-in windowing system targeting
ChromeOS
UI service
Legacy IPC -> Mojo
Igalia was targeting linux desktop
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10. Timeline
2017: discussions with Google (rjkroege@, reveman@
at FOSDEM)
Bring up and prototype (downstream)
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11. Timeline
2018: discussions with Google (sky@ rjkroege@)
Rework on top of Aura/Views
Begin of upstreaming ozone/wayland fork
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13. Timeline
2019: Consolidation of the existing X11 code and
ozone/x11
2019: Wayland/Host and Wayland/GPU
refactoring of the ozone/drm to share GBM related
code
2020-2024: Lacros
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14. Lacros timeline
goal: decouple browser from window manager on
ChromeOS
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15. Lacros timeline
2015:
2020: start of Lacros?
first Exo commit
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16. Lacros timeline
what happened between 2020 and 2024?
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17. Lacros timeline
2024
finch trial
users can opt-in
lacros support
lacros only
lacros primarily
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18. Current status
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19. Current status
Wayland support still experimental, must be enabled
manually: --ozone-platform=wayland /
--ozone-platform-hint=auto
incomplete list of things that were fixed:
screen sharing (without audio)
basic IME
interactive_ui_tests
window decorations, rounded corners
hardware acceleration
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20. Demo time!
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21. Moving towards
stabilization
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22. Stabilization blockers
areas that still need work:
drag and drop
(fallback) tab dragging
fractional and mixed scaling
IME
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23. Questions?
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