Reproduction steps:
1. Open the attached “IN-107834.zip” project
2. Open the “SampleScene”
3. Open the “Tile Palette” Window (Window > 2D > Tile Palette)
4. Make sure the Active Palette is set as “autotile test”
5. Select the Brush (or press B on the keyboard) and the Tile
6. In the Scene view, draw with a Brush at least a 3x3 area
7. Select the drawn Tilemap and observe the Colliders

Expected result: The centre green Tile does not have any Colliders
Actual result: The centre green Tile has a TilemapCollider

Reproducible with: 4.2.1, 5.0.1 (6000.1.12f1, 6000.2.0b10, 6000.3.0a3)
Couldn’t test with: 6000.0.54f1 (AutoTile functionality not available)

Reproducible on: Windows 11
Not reproducible on: No other environment tested

Notes:
- The green tile - “legacy_atlas_6603.asset”, has its Collider Type set to None
- Placing the tiles manually from the Tileset, makes the colliders react as expected and does not reproduce the issue