Cannot read property 'removeEventListener' of null

[maxymczech]

Hello. Lately I have been getting this error message from ember-cli-flash in Sentry console of a project, error comes from addon-tree-output/ember-cli-flash/components/flash-message.js:

    willDestroyElement() {
      this._super(...arguments);
      this.element.removeEventListener('mouseenter', this._mouseEnter);
      this.element.removeEventListener('mouseleave', this._mouseLeave);
    }

Is it possible to wrap this call in if (this.element) { ... }?

[sbatson5]

Thank you for posting. This should be fixed now by #315