Javascript - I can't create my lightbox, forEach is undefined

Question

Hello,

I have a problem with my lightbox, when I'm trying to link my lightbox folder (lightbox.js) to the photographerPage (photographerPage.js line 56), it says that "forEach" is undefined, and I don't know why.

I don't know if someone can help me with that.

Here is the code (GitHub Pages) : https://axsf3.github.io/FishEye/photographer-page.html?id=243

Thanks in advance.