Duplicate template suggestions

Hello,
I want to custom the output of users with twig suggestion, but
I get the 2 times the suggestion "layout--onecol.html.twig" for the "One column" layout, so I can't use the "layout-onecol--user.html.twig" file for example...

Extract from the debug mode:

<!-- THEME HOOK: 'layout__onecol' -->
<!-- FILE NAME SUGGESTIONS:
   x layout--onecol.html.twig
   * layout-onecol--user--1.html.twig
   * layout-onecol--user-user-full.html.twig
   * layout-onecol--user-user.html.twig
   * layout-onecol--user-full.html.twig
   * layout-onecol--user.html.twig
   x layout--onecol.html.twig
   * layout.html.twig
-->
<!-- BEGIN OUTPUT from 'core/modules/layout_discovery/layouts/onecol/layout--onecol.html.twig' -->

Do you hnoxw why ?

I use D8.3.2, layout_discovery, ds 8.x-3.0

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Further investigation shows that:

1. This happens also for field node created, comments, links and the toolbar.
2. This also happens without layout_discovery enabled.