TeamCity REST can be configured to allow cross-origin requests.
If you want to allow requests from a page loaded from a specific domain, add the domain page address (including protocol and port) to comma-separated internal property
To enable support for preflight OPTIONS request, add "rest.cors.optionsRequest.allowUnauthorized=true" internal property.
If that does not workhelp, enable debug logging and investigate the log and look for related messages. If there are none, capture the browser traffic and messages to investigate the case.
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