getFileAsync does not succeed for Excel in WOPI

[SirDavenport]

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Your Environment

• Office on the web
• Excel
• Build: 16.0.18522.42300
• Windows
• Microsoft Edge

Expected behavior

We have an addin with a button that calls Office.context.getFileAsync and we expect that to succeed so we can upload the workbook.

Current behavior

When the button is clicked and getFileAsync is called, the result is not a success and we get this error
code: 11001
message: "A network problem has prevented retrieval of the file."

Steps to reproduce

1. Have an addin that has a button that calls getFileAsync.
2. Open an excel document in Wopi.
3. Open the addin in the Excel document.
4. Click the button.
5. See the error.