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Thank you, I still need a bit more help. In the function, I need to specify the ajax library, for example: import { req } from 'superagent'; and a PHP feed: req.get('myxmlfeed.php').

How do I indert the hebcal feed?
Maybe you have a working example of this? Thank you for your help!

Yes it does! I'm very impressed, Hebcal is really advanced! Thank you so much for your help, I hope I will be able to implement it easily.
Thank you for your quick answer, you really helped me!