Admin_level=9/10 boundaries are too similar to disused railways and paths

[jeisenbe]

Expected behavior

• Administrative boundaries (boundary=administrative) should not be similar to on-the-ground features
• All rendered admin_level=* values should be clearly distinct

Actual behavior

• railway=disused features are very similar to boundary=administrative + admin_level=9 or admin_level=10 (which have the same rendering)
• Hat tip to @Tomasz-W for noticing this in Unify railway rendering #2872 (comment)
• The widely-spaced, dotted gray line also might be mistaken for a type of highway=path or =footway with access=no or under construction

Links and screenshots illustrating the problem

https://www.openstreetmap.org/#map=17/52.37805/16.90282

https://www.openstreetmap.org/#map=18/52.37779/16.83689

https://www.openstreetmap.org/#map=18/52.37546/16.83968

[jeisenbe]

Anyone have a good example of an under-construction or access=private path next to one of these? I thought I had seen one yesterday in another issue but can't find it now.

[kocio-pl]

I guess we could add wide ending of the lines, since this is common rendering of borders on different maps and we're gonna use this only for pipelines probably (and even then it would be double line - see from the #640 (comment)).

I'm not suggesting just adding it to the al9 (and al7, since this is the same as al6 IIRC), but rather add this as another tool in our toolset.

[newtestaccount4949]

Also, level 6 looks a lot like tracks (see https://www.openstreetmap.org/#map=15/55.7010/-4.3341)

[HolgerJeromin]

screenshot for linked map area:

[jeisenbe]

Fixed by #4100, I believe