FAQ: Mounting Lifecycle Methods - componentDidMount

This community-built FAQ covers the “componentDidMount” exercise from the lesson “Mounting Lifecycle Methods”.

Paths and Courses
This exercise can be found in the following Codecademy content:

Web Development

Learn ReactJS: Part II

FAQs on the exercise componentDidMount

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the “alert(‘YOU JUST WITNESSED THE DEBUT OF… FLASHY!!!’);” appears before rendering, even though I put it within the componentDidMount() property

I have the same issue. Is this CodeCademy’s bug?

So far just about everything in the advanced react course has already been completed. Every box that you can check has been checked and all the code has been completed for me. A bit counter productive.

This is not a Codecademy’s bug.
Tried it in a sandbox of React, and the same happens.

Seems to have a disconnection between rendering and actually displaying the content of the DOM on screen. I searched a lot for it on Google, but found nothing so far.
Some clarification from the authors would be appreciated.