v153 · spell check dictionary
An editor with a project glossary
A real editable field with spell checking on, and a real term list beside it. Everything about this page works today except the one call that matters — and rather than pretend, it shows exactly which words it would have sent and what it cannot find out afterwards.
The document
Your browser is checking this field right now. The words the glossary lists are almost certainly underlined — and there is no way for this page to confirm that, because spell-check results are not exposed to script. That asymmetry is the point: a page can add words to the dictionary but can never see the effect, which is what makes a write-only API acceptable rather than merely convenient.
The project glossary
What this page did
The journal records the exact call, whether or not it could be made. That is the only honest form a demonstration of an unavailable API can take: the arguments are real, the intent is real, and the line says plainly whether the browser received it.
What you would do instead, today
The workaround everybody reaches for is spellcheck="false" on the field. It removes the false positives and the true ones together, so a release note goes out with "recieved" in it because the browser was told to stop looking. Try it — the checkbox below sets the attribute on the real field above.