Attach (recommended) or Link to PDF file here:

Configuration:

• Web browser and its version:
• Operating system and its version:
• PDF.js version:
• Is a browser extension:

Steps to reproduce the problem:

1. on file viewer.js
   

   pdf.js/web/viewer.js

   Line 214 in 4fe9260

   event.initCustomEvent("webviewerloaded", true, true, {});

   
   listen event and motify appOptions

2. on file app.js

   pdf.js/web/app.js

   Line 741 in 4fe9260

   const apiParameters = AppOptions.getAll(OptionKind.API);

   get config for api

3. but app_options.js has not option for httpHeaders ,

   pdf.js/src/display/api.js

   Line 192 in 4fe9260

   function getDocument(src) {

   support this option

What is the expected behavior? (add screenshot)

suport custom httpHeader for viewer.js
i can only hook xhr, fetch for hack this moment.

What went wrong? (add screenshot)

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):