How to reproduce:
1. Create a new Unity project using the Universal 2D template
2. In the Project window, right-click -> Create -> 2D -> Tiles -> Hexagonal Rule Tile
3. Select the created Asset
4. In the Scene view, observe the "Open Tile Palette" Overlay
Expected results: The "Open Tile Palette" menu item fills the full width of the Overlay
Actual results: The "Open Tile Palette" menu item is narrower than the Overlay, leaving a gap on the right side
Reproducible with: 6000.2.0b2, 6000.3.17f1, 6000.5.10f1, 6000.6.0f1, 6000.7.0a6
Not reproducible with: 6000.0.81f1, 6000.2.0b1
Reproducible on: macOS Tahoe 26 (M1)
Not reproducible on: No other environment tested