Sidebar doesn't persist

I click on the pin to not hide the sidebar, but if I refresh the page the setting is forgotten.

<img width="257" height="288" alt="Image" src="https://github.com/user-attachments/assets/6ff95d4f-a6af-43ea-8273-e3003f060f4a" />

Version: `squaremap-paper-mc1.21.11-1.3.12`