Fix a reconnecting popup and avoid losing unsaved changes

When the reconnecting popup appears, reloading warns that some changes may not be saved and loses anything made after the connection became unstable.

1. Reloading the page shows a warning that some changes may not be saved.

   ✓ 已于 2026年10月11日 在产品中核实

2. If you reload anyway, the changes made after the connection became unstable are lost and the design may be published without them.

   ✓ 已于 2026年10月11日 在产品中核实