You can find this information here:
https://itch.io/docs/creators/html5#zip-file-requirements
- The size of all the extracted content should not be greater than 500MB.
- The size any single extracted file should not be greater than 200MB.
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So right now, having a file larger than 200 MB already breaks the project.
I think it would be good if this were mentioned in future Game Jams. But well, experience for next time.

