Contrib levelset menu not appearing after finishing or exiting level

[Vankata453]

SuperTux version: 0.6.3 System information: Windows 10

Expected behavior

The contrib levelset menu, which appears when a levelset without a worldmap is chosen, should not be closed, or should re-appear, when a level from the levelset is finished or exited.

Actual behavior

On level exit, the main menu appears.

Steps to reproduce actual behavior

Open a levelset without a worldmap from the "Contrib Levels" menu, and load one of its levels. Exit or finish the level and notice the main menu appearing after the level closes.

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This is a very minimal issue. However, it causes poor UX, because of the user having to always re-enter the menu to play another level in the levelset.

[Semphriss]

Related, but (probably) separate: Whether or not exiting from worldmaps, the Story Mode, the level editor, and any other potential "sub-screen" should re-open the last menu that was used to access it, in the same fashion as levels from levelsets re-opening their corresponding menu.

I would not recommend doing as such, since exiting from a worldmap to the main menu is expected to bring, well, the main menu itself, and it would be tiresome to manually exit the menus one by one. Also, after moderately long gameplay times, the user might not remember where they were in the menus, which requires an extra mental effort before navigating the menus.

I do not extend my recommendation in the case of levelsets; I have no problem imagining the expectations of "staying contained" within the levelset, such as someone looking for a certain level and trying them one by one, or even just someone who downloaded a brand new add-on and wants to try all the levels consecutively. I only mention it because I suppose the question will inevitably arise at some point, given the similarity in both ideas, and I'd like to stimulate the discussion as early as possible.

[Vankata453]

In my opinion, having the last menu preserved would make sense the most for levelsets, since they don't have their own worldmap and the contrib levelset menu is used to navigate through them.