The labels on Special:WatchlistLabels are sorted alphabetically (if the user clicks to sort by that column, and after T410356 is finished), but on the filter list on Special:Watchlist they're not.

Derived Requirements

1. The label filter list on Special:Watchlist must display labels sorted alphabetically.
2. Alphabetical sorting must be consistent with the sorting behavior used on Special:WatchlistLabels.
3. Sorting must be locale-aware and follow standard MediaWiki collation rules.
4. The sorted order must be applied automatically without requiring user interaction, unless on Special:Watchlist.
5. Label sorting must not affect existing watchlist filtering functionality.

Test Steps

Test Case 1: Alphabetical Sorting of Label Filter List

Preconditions

• The user is logged in.
• Multiple watchlist labels exist with non-alphabetical names (for example: Zeta, Alpha, Beta).

1. Navigate to Special:Watchlist.
2. Locate the labels filter list.
3. Observe the order in which labels are displayed.
4. ✅❓❌⬜ AC1: Verify that labels in the filter list are displayed in strict alphabetical order according to locale-aware collation.

Test Case 2: Consistency With Special:WatchlistLabels Sorting

Preconditions

• Same labels exist on both Special:Watchlist and Special:WatchlistLabels.

1. Navigate to Special:WatchlistLabels.
2. Observe the alphabetical order of labels after you sort it.
3. Navigate back to Special:Watchlist.
4. Compare the label ordering in the filter list.
5. ✅❓❌⬜ AC2: Verify that the alphabetical order of labels on Special:Watchlist matches the ordering used on Special:WatchlistLabels.

Test Case 3: Automatic Sorting Without User Interaction

Preconditions

• Same as Test Case 1.

1. Navigate to Special:Watchlist.
2. Do not interact with sorting or filtering controls.
3. Observe the label filter list on initial page load.
4. ✅❓❌⬜ AC3: Verify that labels are already sorted alphabetically on page load without requiring any user action.

QA Results - Beta