RMD044 — An unknown element type in JSX

A tag has to be a string, a component class, or — for the one unsupported case — a function. This was none of them, so an inert <template> renders in its place and whatever it was meant to be is missing.

Usually a value used where a tag belongs: an object read off a map with the wrong key, or a component whose import failed and arrived as undefined. A function in tag position is a different mistake with its own advice — see RMD011.

The stand-in is rendered in every build, so a failed import costs that one element rather than the page. Reported once per component, so two of these in two files are two reports.

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