Nautilus integration : folders should display also in the save window automatically

Since version 3.10 the sync folders are shown in the bookmark area from nautilus automatically. This is a nice feature but incomplete.
When we want to save a file, sync folders are NOT shown in the bookmark area.


If we want them to be displayed, we should add them manually as bookmarks but then, it means they would display two times in Nautilus...


Could sync folders be shown in the bookmark area in the "save file window" automatically too?

Or then as requested in this issue could the automatic feature become an option as requested here : https://github.com/nextcloud/desktop/issues/6130

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### Feature description
Tell us how the feature should work