Refuses, for users without unfiltered_html, non-Divi blocks, raw text parts,
unreadable opaque blocks, code modules, builder-only paths (also below the
state value), strings that are not sanitizer-stable and stored $variable
references that VariableRef::canonical() refuses or would change (P2, P3).
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>