"File extension not supported" on uploading .md files in workflow

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Dify version

1.0.0

Cloud or Self Hosted

Self Hosted (Docker), Cloud

Steps to reproduce

An error message appears: "File extension is not supported" on uploading a .md file in a workflow Some mistake on getting extension from mime, I think

Reproduction

• Platform: self hosted(docker), cloud.dify.ai
• Support File Types: Document, Custom(add .md)

✔️ Expected Behavior

No response

❌ Actual Behavior

No response