curl query to regular url: basic auth

I’m currently experimenting with the Toggl API

For example, the page states

curl -v -u 1971800d4d82861d8f2c1651fea4d212:api_token -X GET 

If i enter this in my console (using my api token, not the example token of course) it works and I’m getting back the requested JSON.

If I try to get the json however directly in a browser by restatting the query as 

I’m getting

Access to was denied You don't have authorization to view this page. HTTP ERROR 403 

what am I doing wrong? I thought that user:pw@domain would be the same as curl -u user:pw -X GET domain