ZIM status polling from Selection list page seems broken

I'm seeing requests in the console for:

127.0.0.1 - - [23/Mar/2025 09:54:09] "GET /v1/builders/undefined/zim/status HTTP/1.1" 200 -

Obviously undefined should be the ID of the builder. This means that if a user is watching the Selection list page, their ZIM file will never update as "finished" unless they refresh the page.