Steps:

• Select some artists in the relationship editor.
• Merge that artist to another artist and wait until vote period.
• Try to add some artist-related relationship.

according to DevTools network tab, JS try to load specific artist, but server returning different MBID artist, since that entity is already merged to another entity. but JS wouldn't handle it correctly and just reloads it infinitely.

in this state, you can see specific artist in the recent items, multiple times.
also search would not work (waiting recent items loading forever)

Workaround: we can escape from this state by click "Clear recent items", but it would be hard to click (depends to your internet connection and MB's server response speed) because recent items will be added after each retry API requests (you might be want to make your browser offline first, by DevTools or just unplug LAN cable / disable Wi-Fi).

Environment: Firefox Nightly 143.0a1 (2025-08-10) @ macOS 15.6 arm64