JavaScript files in static folder are not delivered

🐛 bug report

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Description of the problem

I created a Code Sandbox with the TypeScript starter. I added a static folder and placed two files in there. The file bla.js and test.txt. When I try to fetch those files only test.txt is delivered. As you can see here:

• https://zvik0.csb.app/static/bla.js --> fails
• https://zvik0.csb.app/static/test.txt --> works

How has this issue affected you? What are you trying to accomplish?

I need to load a js file from the static directory. The example from above is only a toy-example to illustrate the issue but in reality I try to load a JavaScript module that was compiled from C/C++ with emscripten to JavaScript.

To Reproduce

Try to access one of the following files:

• https://zvik0.csb.app/static/bla.js --> fails
• https://zvik0.csb.app/static/test.txt --> works

Link to sandbox: link

Reproduce the behavior with the linked sandbox and compare delivery of /static/bla.js with /static/test.txt. Trace the static-file delivery entry point to find why JavaScript files are rejected or omitted. Done means JavaScript files in a sandbox's static folder are fetchable like the text file.