Igalia’s Max Ihlenfeldt summarizes the work and difficulties of allowing window dragging and merging in the Wayland compositor.

1. Fallback Tab Dragging for
Ozone/Wayland
Max Ihlenfeldt <max@igalia.com>
2022-11-15 @ BlinkOn 17

2. Fallback Tab Dragging for Ozone/Wayland
Max Ihlenfeldt, 2022-11-15
X11 tab dragging

3. Fallback Tab Dragging for Ozone/Wayland
Max Ihlenfeldt, 2022-11-15
Wayland tab dragging

4. Why doesn’t it work on
Wayland?
● Wayland clients don’t know about global screen coordinates
● Wayland clients can’t control the window position on their own
● ⇒ can’t move the window containing the detached tabs with the cursor
Fallback Tab Dragging for Ozone/Wayland
Max Ihlenfeldt, 2022-11-15

5. Extended drag
● Wayland protocol extension by Nick Diego
● Extends DnD capabilities to implement regular tab dragging
● Currently only supported by Exo
Fallback Tab Dragging for Ozone/Wayland
Max Ihlenfeldt, 2022-11-15

6. Fallback Tab Dragging for Ozone/Wayland
Max Ihlenfeldt, 2022-11-15
Fallback tab dragging

7. Testing is hard
Fallback Tab Dragging for Ozone/Wayland
Max Ihlenfeldt, 2022-11-15
● Input emulation problems on Wayland when multiple browser windows are open
● New Wayland testing protocol extension in the works
● Until tests pass: behind feature flag
AllowWindowDragUsingSystemDragDrop

8. Thanks!
Thanks to:
● Scott Violet
● Nick Diego
● Erik Chen
● Mitsuru Oshima
Fallback Tab Dragging for Ozone/Wayland
Max Ihlenfeldt, 2022-11-15