Production Preview stage profile

This host-only probe executes the production BrowserService.NavigateDocument, original bundled website scripts, live event loop, CSS layout and offscreen GDI+ canvas. It separates HTML generation, navigation/script execution, first layout, cached paint and eight scroll paints. It does not measure a QEMU guest, native framebuffer, GPU or CUDA. Timings from this probe must not be presented as native frame rates.

Run from the repository, using a unique absolute artifacts path:

dotnet run --project Tools/BrowserCompatibility/PreviewProfile/PreviewProfile.csproj -c Release --artifacts-path C:/Absolute/Unique/Build -- C:/Absolute/XFESystem Baseline

Each run retains a unique build/PreviewPerformance/<label>-<timestamp>/Result.json. The receipt includes actual resource requests, every script begin/end trace, CSS parse/reuse counts, packaged prepared-syntax hits, compiled assembly hash and source hashes. Three fresh page engines per fixture exercise cold and warm script syntax while keeping their DOM/globals independent.