ERROR An error happened during Keycloak initialization

I’m trying to use

try {
  await keycloak.init({
    config: {
      url: 'https://xxxx.com/auth',
      realm: 'xxxxx',
      clientId: 'account',
      credentials: {
        secret: 'xxxxxx-980a-4588-a846-xxxxxxx'
      }
    },
    initOptions: {
      onLoad: 'login-required',
      checkLoginIframe: false
    },
    bearerExcludedUrls: [
      '/assets'
    ]
  });
  resolve();
} catch (error) {
  reject(error);
}

in the browser see this error:

ERROR An error happened during Keycloak initialization.         core.js:1448
defaultErrorLogger                    core.js:1448
ErrorHandler.prototype.handleError    core.js:1509
_callAndReportToErrorHandler/</<      core.js:5682:54
ZoneDelegate.prototype.invoke         zone.js:388
Zone.prototype.run                    zone.js:138
NgZone.prototype.runOutsideAngular    core.js:4697:47
_callAndReportToErrorHandler/<        core.js:5682
ZoneDelegate.prototype.invoke         zone.js:388
onInvoke                              core.js:4749
ZoneDelegate.prototype.invoke         zone.js:387
Zone.prototype.run                    zone.js:138
scheduleResolveOrReject/<             zone.js:858
ZoneDelegate.prototype.invokeTask     zone.js:421
onInvokeTask                          core.js:4740
ZoneDelegate.prototype.invokeTask     zone.js:420
Zone.prototype.runTask                zone.js:188
drainMicroTaskQueue                   zone.js:595
ZoneTask.invokeTask                   zone.js:500
invokeTask                            zone.js:1517
globalZoneAwareCallback               zone.js:1543

also:

Pedido de origen cruzado bloqueado: La política de mismo origen no permite leer el recurso remoto en https://xxxxx.com/auth/realms/xxxx/protocol/openid-connect/token. (Razón: encabezado CORS 'Access-Control-Allow-Origin' faltante).

this causes that the web does not load.

[sateliermartin]

I found out what the error is.

The error is CORS ‘Access-Control-Allow-Origin’.

To test it, disable Cross Source Restriction in the Safari browser and it worked correctly.

[sateliermartin]

The configuration of keycloak is standard, do not make any special configuration and the clientId and secret are correct.

analyzing the code, go to line 546 of keycloak.js:

if ((kc.flow != 'implicit') && code) {
    var params = 'code=' + code + '&grant_type=authorization_code';
    var url = getRealmUrl() + '/protocol/openid-connect/token';

    var req = new XMLHttpRequest();
    req.open('POST', url, true);
    req.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');

    if (kc.clientId && kc.clientSecret) {
        req.setRequestHeader('Authorization', 'Basic ' + btoa(kc.clientId + ':' + kc.clientSecret));
    } else {
        params += '&client_id=' + encodeURIComponent(kc.clientId);
    }

    params += '&redirect_uri=' + oauth.redirectUri;

    req.withCredentials = true;

    req.onreadystatechange = function() {
        if (req.readyState == 4) {
            if (req.status == 200) {

                var tokenResponse = JSON.parse(req.responseText);
                authSuccess(tokenResponse['access_token'], tokenResponse['refresh_token'], tokenResponse['id_token'], kc.flow === 'standard');
            } else {
                kc.onAuthError && kc.onAuthError();
                promise && promise.setError();
            }
        }
    };

    req.send(params);
}

req.status is 0

Any other idea to be able to find the problem.