Content past 16 MiB says so, and content that does not decode strictly says that: autotag_text_says_why_it_cannot_read_a_page. Mutation testing found nothing pinned which message each gets.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY