TYPO3 Core

This issue occures in 11.5.30 as well as in 12.4.4.

When the internet connection is too slow, the category tree does not load. Instead the JS console shows this error:

Uncaught (in promise) TypeError: Cannot read properties of null (reading 'dataset')
    at SelectTreeElement.generateRequestUrl (select-tree-element.js?bust=570e49c9f4853b50cd9289267f625c76f9c5f218:13:2301)
    at new SelectTreeElement (select-tree-element.js?bust=570e49c9f4853b50cd9289267f625c76f9c5f218:13:1423)
    at java-script-item-processor.js?bust=570e49c9f4853b50cd9289267f625c76f9c5f218:13:1629
    at java-script-item-processor.js?bust=570e49c9f4853b50cd9289267f625c76f9c5f218:13:1720
    at Array.map (<anonymous>)
    at java-script-item-processor.js?bust=570e49c9f4853b50cd9289267f625c76f9c5f218:13:1710

How to reconstruct:

1. Install EXT:news
2. Create some categories (I've created two root categories and one sub category. In total 3 categories) on root level
3. Create a news record and save it
4. Throttle your internet connection, using Developer Tools in e.g. Chrome:

In case, the default profiles (Fast/Slow 3G) are not slow enough, create a new profile. With the following settings I was able to reconstruct this issue almost every time, on an empty, fresh TYPO3 installation within DDEV:

Then refresh the frame: