What goes first foundation or concealer?

What goes first foundation or concealer?
Q: If you're using both foundation and concealer, which goes on first? ... For those with few or no blemishes, a light dab of concealer before foundation might be just enough. However, for makeup artist Daniel Martin, foundation always comes first because it allows him to see which areas on the face need more coverage.

Reference:
Lunchtime Beauty Q&A: Which Goes on First, Foundation or ...
May 15, 2019

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