Demo environment is broken

### What is the input mode? Mouse ### What type of issue is it? Functionality ### What happened? The demo environment seems to have some issues: https://openrailassociation.github.io/netzgrafik-editor-frontend/ <img width="762" height="526" alt="Image" src="https://github.com/user-attachments/assets/46a6adb7-9704-446f-92d2-214cfa09d593" /> ### What did you expect to happen? _No response_ ### How can we reproduce it (as minimally and precisely as possible)? https://openrailassociation.github.io/netzgrafik-editor-frontend/ ### On which environments the bug occurs? Local ### On which browser the bug occurs? Firefox ### Netzgrafik-Editor version (top left corner `Version x.yy.zz`) 2.10.19