(TypeError) : Cannot read property 'removeConnector' of undefined on '$0, r

Hello Everyone,

I have a view with a @Push config, that works fine 99% of the time, but sometimes I get the following error:

(TypeError) : Cannot read property ‘removeConnector’ of undefined
_f @ vaadinPush.js?v=2.1.9:2765
_invokeFunction @ vaadinPush.js?v=2.1.9:2754
_invokeCallback @ vaadinPush.js?v=2.1.9:2884
_websocket.onmessage @ vaadinPush.js?v=2.1.9:1457

client-C4F9B966016EDC8B1F7B7E1211C8B1A7.cache.js:202 The error has occurred in the JS code: ‘$0, return $0.$contextMenuConnector.removeConnector()’

I created the view following this guide:
https://vaadin.com/docs/v14/flow/advanced/tutorial-push-access.html

I would appreciate any help,
Thanks in advance,
Regards.