Include the mixed-size flag in the font-size draft cache key. Selecting a mixed block can preserve the previous representative number, so a value-only key left the field showing 24 instead of Mixed. Unchanged formatting still preserves partially typed input across frames.
The headless regression covers uniform-to-mixed and mixed-to-uniform transitions with the same number, draft preservation and a single committed edit. Linux scoped clippy, tests, wasm, formatting, layering and assets pass; reverting the cache fix reproduces the stale display.
Co-Authored-By: Codex GPT-6.1 <noreply@openai.com>