Unwrangling from original parent task. Language team should follow up when MW core support is given.

There is no blocker for moving forward with this.

@Nikerabbit Could you expand? All Language team maintained products should remain for the time being is what I've understood. If it's a child task, then it's a blocker for resolving the parent task. That's why I remove the three products as child tasks.

@Nikerabbit Could you expand? All Language team maintained products with their MW 1.39 support should remain for the time being is what I've understood. If it's a child task, then it's a blocker for resolving the parent task. That's why I remove the three products as child tasks.

The proposed change does not break compatibility with older MediaWikis (only for older browsers), so it can be done. Also, because we now support 1.39 or later in Translate and ULS, there is no argument to keep same support as MW as MW itself has dropped it.

Also, TwnMainPage is not having the special compatibility policy, though it's not deployed to WMF either.