I am convinced there should be a warning displayed whenever user puts a file or a folder inside a shared folder because it will be immediately shared with others (public). There could be user error where file is incorrectly moved for whatever reason into the shared folder and all sensitive files are exposed.

Picture: Moving a whole folder of sensitive files inside a shared folder, shares the folder recursively to the public.
is very simple, simply print a warning dialog whenever (picture) that occurs.
Nextcloud version: (see Nextcloud admin page)
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cc @nextcloud/designers @nextcloud/sharing
I think this is not a bug but an enhancement.
The correct way to do this is not show a warning, but for every move there should be a confirmation saying:
Moved Sensitive files into Shared documents [ Undo ]
I disagree, but it's still better than nothing. (See Google Drive for reference)
(See Google Drive for reference)
@pilsnerbeer could you share screenshots of the process of how Google Drive handles this? That would be very helpful. :) Maybe also Dropbox, if you have it at hand.
How would we know which files are sensitive?
could you share screenshots of the process of how Google Drive handles this?
Here's how Drive handles it when you try to drop any file/folder inside a shared folder:
(this is a dialog)

How would we know which files are sensitive?
Perhaps I haven't explained well enough- all files/folders are treated as "sensitive" when it comes to putting them in a folder which would expose it to the public - for that reason, confirmation is required to proceed with sharing
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Here's how Drive handles it when you try to drop any file/folder inside a shared folder:

(this is a dialog)
Perhaps I haven't explained well enough- all files/folders are treated as "sensitive" when it comes to putting them in a folder which would expose it to the public - for that reason, confirmation is required to proceed with sharing