I originally marked this issue as a security because of the links to the other security issues, however those are now closed and this is more of a security improvement.

Specifically in Workplace we want to change the defaults so no tags are displayed in the tag cloud on /tag/search.php as a default.

Not a lot of people even know about the existence of this page and since we changed navigation in theme Boost there are no direct links to this page. However it exists, it does not require any capabilities and it also can be found by:

• add a user interest in your profile
• view your profile and click on the tag with your interest
• now you see a page that shows all entities on the site that are marked with this tag (most likely only your own profile). There are permissions checks that make sure that you do not see things that you do not have access to
• on this page in the breadcrumb you can navigate to the "Tags" page which is /tag/search.php
• this page by default displays all tags in all tag areas ever used, without any permission checks, this can be courses, user interests, etc.

Admin can go to "Site administration > Appearance > Manage tags" and create additional tag collections, mark them as not searchable and move some sensitive tag areas there.

However admin can not make the "Default collection" not searchable.

Why I want to make this improvement:
In Workplace we use tags a lot and we also have multi-tenancy, showing the list of all tags to all users is really not desirable. We would like to automatically make "Default collection" not searchable when a Workplace site is installed. Admin should be able to change this default later. I also assume that 99% people don't even know about this page, so it brings no benefit but has potential security considerations.

I would recommend to make any tag areas non-searchable by default in LMS as well