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It could be a dummy question, but I'm a little obsessive with the order and organization. I use TeXstudio as editor, so when I call the packages, generally the commands associated to them appears as suggestions when I write. However, TeXstudio mark as wrong some commands even when I called the package. There are 2 examples for the packages siunitx and makecell:

Here, the command \makecell from makecell package appears as wrong and the centimeter option \cm from siunitx too. It's important to say that I have no problems compilating, it's just an obsession.

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How can I let TeXstudio to recognize this commands (and others that I can't remember) and show them in the siggestions too?

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marked as duplicate by Troy, TeXnician, CarLaTeX, Stefan Pinnow, Andrew Sep 29 '17 at 7:23

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