WebCore issues when using Safari

We have developed a web application and use XData and WebCore. Under Windows, Android the connection to the XData server works. In Safari we get the error message "Failed to load Resource"

any ideas

Sorry but this is a very vague description. Without knowing any detail about your application, what is happening, what exact functionality is used, I cannot really guess what could be going on here.

I can understand it, without concrete information it is difficult to find the cause.

There must be a problem with the XData server, swaggerui cannot be accessed via Safari. This is easily possible via Chrome, Firefox.

I currently have no idea where to start looking.
Could narrow the problem somewhat. The model cannot be called up in Safari.
http://xxx.xxx.de/orderportal/data/$model

Error 503 "Service unavaible" is sent.

It doesn't make much sense that you get a error 503 from Safari but not from other servers. 503 means an error in the server. The XData server doesn't handle anything that is browser-specific.

"Service unavailable" means just that: the server is not available, either it's not working properly, or you tried to access an invalid address (URL).

Can I send a test URL to the support mail? The different behavior can be reproduced via this URL.

Yes, please contact support by email