Otherwise the example of the hotspot is a good alternative, especially for a tooltip in a 3D world. You just have to modify the script to enable a text element when a hotspot is pressed and disable it after release.
Honestly, I would try a Textelement on a 3D Screen in world space instead of using CSS.
Check out this project:
https://developer.playcanvas.com/en/tutorials/world-space-ui-rendering-on-top/
Absolutely! Used it in my typing game. Check the vid:
https://forum.playcanvas.com/t/random-wip-bullshittery/12943/23?u=sebastian
Ah good to know. I will need that later when I continue to work on the UI in my game. Does it work the same way as with an image element?
Text and Image elements are pretty much comparable so, yeah 
So how do you do that for text? It’s not working at the moment…
Adding the no depth on text… 
I think we have some miscommunication. The project you showed was a example of how to render an image on top of a world entity. I like to do that also with text. Thanks anyway. 
Ha! No worries
If you look at the project now, I added an extra text element on top of the cube entity. Sure it still needs a proper lookAt function but otherwise, it works 
What I mean is when there is an object in front of the text the text is still visible. Probably I have to add an extra camera that only renders the text.
Yes, that’s it! Thanks! 
You can listen for click events on your hotspots and then simply enable/disable a UI element for the popup.
UI examples:
https://developer.playcanvas.com/en/tutorials/?tags=ui
Please stop creating new topics for the same issue.