legacy_<version>.pk3 is the engine's own build output, named from git describe and different for each release and architecture (ETLBuildMod.cmake:301-316, ETLVersion.cmake:120-131). It is installed with the engine, not downloaded on first run as the note said.
Profiles, the wiki, comments, docstrings, command output and schema descriptions carried em-dashes, clause-joining semicolons, unicode arrows, box-drawing banners and check-mark glyphs. Each sentence was rewritten rather than having its character swapped. Hashes, paths, source_ref values and every cited file:line are unchanged, which a comparison of each parsed profile against the previous revision confirms.
validate_pr comments now say PASS and FAIL in words, and source_ref values in a profile's structured blocks render as code. test_prose_style fails if any of these comes back, in tracked files or in the generated site.
Abdessamad Derraz