Cannot edit new file

If I create a file in the Explorer app (for example, file.md) and open it in the Mark-Reader app, it gets stuck in rendered mode and shows the file as empty. I have attached a screenshot. It would be great if I could edit the file.

<img width="1280" height="2772" alt="Image" src="https://github.com/user-attachments/assets/6c2aee8b-acb4-4c1e-bb8f-801734895436" />