Component cannot be used as JSX Component. Its Instance type is not a valid JSX element

Yesterday, in a separate folder, I initialized CRA + installed Material UI. Unfortunately (I think) this made me sprinkle the rest of the projects in separate folders. I think I've searched all over the internet. I used "resolutions", nothing helps.... Of course, I cloned the repository, removed node modules, installed again and so on. package.json file: https://pastebin.com/gcpHbbmh Thanks guys

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"name": "app", "version": "3.1.4", "private": true, "typings":...

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