Should I be concerned by "SecurityError: Permission denied to access property on cross-origin object" logs

Question

Following errors were logged on my website, should I be concerned or can I just ignore them?

SecurityError: Permission denied to access property "dispatchEvent" on cross-origin object - url: moz-extension://f985b107-bcb9-45d4-95c4-b1bb39443725/js/inject.js - line: 65 - column: 0 - error: SecurityError: Permission denied to access property "dispatchEvent" on cross-origin object (browser: Firefox 55) 

Thanks!

Answer 1

You should not be concerned, you can ignore them.

It comes from extension of a firefox browser: url: moz-extension://f985b107-bcb9-45d4-95c4-b1bb39443725/js/inject.js who's trying to attach event but CrossOrigin query is not allowed.

Good documentation explaining CORS (Cross Origin Resource Sharing) : https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS