PDF content in iframe is blocked by browser

[sven09]

This issue is for a: (mark with an x)

- [ ] bug report -> please search issues before submitting
- [ ] feature request
- [ x] documentation issue or request
- [ ] regression (a behavior that used to work and stopped in a new release)

Minimal steps to reproduce

I installed the system according to setup information
I got a chrome-error://chromewebdata/, means the browser blocked showing the content within the iframe for pdfs.

I already tried to allow CORS : "*" on storage, without success

Any log messages given by the failure

no

Expected/desired behavior

Some information how to fix this.

OS and Version?

Chrome & Edge

Versions

latest

Mention any other details that might be useful

Thanks!