CORB blocking fetch() in whilelisted origin

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CORB blocking fetch() in whilelisted origin

Postby isaacsmile » Thu Aug 22, 2019 10:05 pm


I'm using Javascript loaded on a custom scheme to fetch JSON from a server, which doesn't return CORS headers.

Previously it was working with appropriate CefAddCrossOriginWhitelist calls, e.g. CefAddCrossOriginWhitelist("customscheme://customhost", "https", "", true);

However now I get CORB blocked warnings (I'm using CEF on Windows with cef_binary_75.1.14+gc81164e+chromium-75.0.3770.100)

For reference my Javascript looks like:

const data = new URLSearchParams();
data.append('exampleKey', 'exampleValue');
fetch('', { method: 'post', body: data }).then((response) => {
if (response.ok) {
return response.json();

The error I'm getting in the dev tools console is the following:
Cross-Origin Read Blocking (CORB) blocked cross-origin response with MIME type application/json. See for more details

What can I change to allow this response through? Currently it is being changed to an empty string (as described in the CORB document)
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