From Jira7.5, find-polyfill.js is added to provide Array.prototype.find() for old browsers(ex. IE11).

But Array.prototype.find() in this implementation can't be overridden .
Our add-on don't work because the library we use overrides Array.prototype.find() in a subtype of Array.

We hope to be able to override 'find' function like this way.

Also we think Jira had better to do so for the following reasons,

1. The polyfill library(such as babel-polyfill) latest ReactJS encourages is overridable
2. Though modern browsers have native implementation for Array.prototype.find(), they all are overridable