The remaining hydration mismatch was a stray `__gcrremoteframetoken`
attribute added to <html> by a browser extension after the document
loaded. Browser extensions (password managers, accessibility tools, the
Google iframe-token injector, Grammarly, etc.) routinely poke at the
top-level elements before React hydrates and React 19 then flags it as
a mismatch even though our code wasn't involved.
`suppressHydrationWarning` on <html> and <body> only suppresses
**attribute** differences on those elements; their children continue
to be hydration-checked normally, so any real bugs still show up.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
yiekheng
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