Game and addons version
Elvui: 12.24
AddonSkins: AddOnSkins-4.51-8-g2e57837
Details!: DETAILS! VERSION: R8406
Details!: GAME VERSION: v9.0.5

Describe the bug

1. Make two details windows with the embed system of AddOnSkins
2. Put one in Current segment
3. Put the other one in Overall
4. Disconnect and reconnect to the game

Result (what happens when you follow the steps above):
The Overall window is now in Current segment mod
When the Two window embed system is disable, the Overall window stay in Overall mod.

When the bug started (a date, wow path release, details update, etc)?
To my knowledge always been there (at least since BFA).

Other informations
You don't need to disconnect / reconnect to the game to view the issue.
An other way to see the issue:

1. Enable Two window embed system
2. Put one window in Overall
3. Disable then re-enable the Two window embed system
   And now you Overall window is now a current segment one.

I think the segment mod of a window is enforce by the Two window embed system and apply at loggin.

After some digging I think I found the line responsible of the issue:
Embed/Details.lua: Line 139-141:\

if (window:GetSegment() ~= 0) then
	window:SetDisplay (0)
end

When I comment those line the segment state is not reset whith either of those methods.