Describe the bug
When dragging a non-focused tab de behavior is different between Firefox and Chrome:

• Firefox: the tab is focused BUT the drag mode is not activated
• Chrome: the tab is focused AND the drag mode is activated

To Reproduce
dockview demo The bug can be reproduced in the demo

Steps to reproduce the behavior:

1. Open the demo page
2. Do a "long press" in the tab named "Panel 3"
3. Move the mouse (without releasing the click)

Expected behavior
We expect that both browsers behave as Chrome does

Desktop

• Firefox: 138.0.3 (64-bit)
• Chromium 136.0.7103.92 (Official Build) snap (64-bit)

Thank you in advance!