'Attach files' button not working / throwing `Cannot read property 'click' of null` #2774

When clicking the 'Attach Files' button, the file dialog does not open. An error is logged to DevTools console:

content.js:8271 Uncaught TypeError: Cannot read property 'click' of null
    at HTMLDocument.triggerUpload (content.js:8271)
    at HTMLDocument.listenerFn (content.js:369)

Stack trace goes to this line of code in content.js

<img width="595" alt="Screen Shot 2020-02-12 at 3 49 09 PM" src="https://user-images.githubusercontent.com/1271364/74320817-ad47c980-4daf-11ea-97e4-cc22b1c05a99.png">

I can't use the button in this very issue, so I guess this issue url is a good url. 😝

Gif of behavior

When turning off Refined GitHub, the 'attach files' works from plain GitHub.

It's a bit weird because I only noticed this in the last 24 hours, maybe my extensions didn't update until today? Maybe GitHub changed something in their UI. I'm not sure. Let me know if you need anymore information.

Workaround

Disable the 'minimize upload bar' feature from the 'Extension Options' within the 'Details' of the Extension.

<img width="577" alt="Screen Shot 2020-02-13 at 12 06 52 PM" src="https://user-images.githubusercontent.com/1271364/74404644-82b24b00-4e59-11ea-8829-3e9eb81f2f5d.png">