Problem description: when the user selects a couple of item prototypes in the item prototypes table and then switches to Trigger prototypes page, the counter of selected prototypes is not reset:
Example:

Steps to reproduce:

1. Open the list of Item prototypes for any LLD that has both trigger and item prototypes
2. Select a couple of item prototypes
3. Switch to Trigger prototypes page

Result: The counter of selected entries is not reset. When selecting Trigger prototypes, it just keeps increasing.
Expected: The counter of selected entries should be reset when switching between item prototypes and trigger prototypes pages.