Excel custom functions add-in not working

Question

I have been trying to setup an Excel custom functions add-in, but it is not working. These are the steps I took to setup the add-in

1. Run "yo office --projectType excel-functions --name funcy2 --host excel --ts True" (node: 14.18.1, npm: 6.14.15, yo: 4.3.0)
2. Convert project to Shared Runtime
   153696-manifest.xml
   153735-webpackconfigjs.txt
3. Run "npm run build"
4. Run "npm start"

After step 4 the add-in loads partially. The taskpane can be opened, and clicking "Run" in the taskpane works as expected. However custom functions are not loaded. An error message is show that says "One or more add-ins failed to load a required resource." See screenshot below.

Additional information:

Windows
Edition Windows 10 Enterprise
Version 20H2
OS build 19042.1288
Experience Windows Feature Experience Pack 120.2212.3920.0

Office
Microsoft Excel for Microsoft 365 MSO (16.0.13127.21790) 32-bit

It seemed to me from Webpack that all files are served from the root, so I tried removing the dist folder from the custom function meta data and script url, but the result remains the same.

Any help on this would be greatly appreciated.