Each header names its pass and the fixed-function state, blend and formula it reproduces, with the client address; GPU traps, precision rules and marked deviations stay. Bevy's own comments in the two vendored UI shaders stay verbatim so an upgrade re-diffs cleanly. With comments stripped every shader is identical. Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>