Issue Summary

When using the drop-down scroll bar for pagination in the pull request creation interface, the next page of items does not load, resulting in missing entries. This bug might also impact other dropdowns with pagination.

Steps to Reproduce

Step 1

1. Log in as a user with access to more than 26 forks (27 items in this case).
2. Navigate to the pull request creation page.
3. Observe the default selected fork in the drop-down menu.

Step 2

1. Attempt to scroll through the drop-down using the scroll bar.
2. Note that only 25 items are displayed, and the last fork is missing.
3. Check the Network tab to confirm that only one page request is made.
4. Now, scroll using the mouse wheel or touchpad to see the next page loads correctly (dropdown shows all 26 remaining items, excluding 1 selected by default).

Expected Results

The drop-down pagination should load additional items when scrolling using the drop-down scroll bar. All forks (26 remaining items, excluding the 1 selected by default) should be visible regardless of the scroll method used.

Actual Results

When scrolling using the drop-down scroll bar, only 25 items are displayed, and the last fork is missing. Only one page request is made (visible in the Network tab). Scrolling via the mouse wheel or touchpad works correctly and loads the next page as expected.

Workaround

Scroll through the drop-down list using the mouse wheel or touchpad instead of the drop-down scroll bar. This triggers the next page request correctly and displays all items.