Quick answer: Godot 4 TileMap-based world with CharacterBody3D showing micro-jitter on flat ground? Adjacent tile shapes create overlapping edges - use MergeColliders option in TileMap import.
Walking on a tile-floor: subtle vertical jitter every tile boundary.
Enable MergeColliders
TileSet > Physics > Merge Colliders. Edges within tolerance become one shape; no overlap.
Or use a single ground collider
For floor sections, one big collider; tiles for visuals. Avoids the tile-collision interaction entirely.
Raise CharacterBody floor_max_angle
Tolerates angle differences at tile edges. Reduces but doesn't eliminate.
“Adjacent collision shapes have boundary effects. Merging is the cure.”
For tile-based worlds, the merge step is non-optional. Plan the import workflow to include it.