Entities are not displayed when switching between elements in the children tree

Refs requests#655

I can sometimes reproduce this in preprod, prod, demo and on balsac, but never locally 😢

It seems the steps to reproduce the most successfully are:

1. Open an element that has child elements with entities (e.g. a page with multiple paragraphs with transcriptions that have TranscriptionEntities)
2. Click on an element that has a transcription with entities. The entities are displayed.
3. Refresh the page.
4. The entities are still displayed on this element.
5. Click on another element with a transcription with entities. The entities are not displayed.
6. Cry.