Send credentials with GraphQL fetch requests

fetch won’t send cookies in older browsers
unless you set the credentials init option.
See https://github.com/whatwg/fetch/pull/585

Closes https://gitlab.com/gitlab-org/gitlab/issues/36864

app/assets/javascripts/lib/graphql.js

@@ -26,6 +26,10 @@ export default (resolvers = {}, config = {}) => {
     headers: {
       [csrf.headerKey]: csrf.token,
     },
+    // fetch won’t send cookies in older browsers, unless you set the credentials init option.
+    // We set to `same-origin` which is default value in modern browsers.
+    // See https://github.com/whatwg/fetch/pull/585 for more information.
+    credentials: 'same-origin',
   };
 
   return new ApolloClient({

changelogs/unreleased/vs-add-credentials-option-for-apollo-link.yml

+---
+title: Send credentials with GraphQL fetch requests
+merge_request: 26386
+author:
+type: fixed