Seal Collections in outliner
It would be neat to have a way of sealing collections in the outliner.
It could be useful for addons that create a collection for certain assets it is dealing with, but that are unimportant for the users workflow.
So the Root Collection is shown, with a little special symbol but non of its children appear in the outline any more.
However, programatically it should still be possible to edit, add and remove objects to this collection with python.
Clarification:
I propose that you still have the the collection in the scene, visible in the outliner and its content visible in 3D Space.
Just that the collections children are not shown in the outliner anymore.
2 Comments
I'm not sure to fully understand what you mean exactly by "sealing". Do you mean a form of GUI-lock, as in, you can't use the GUI to add/remove/edit things inside a sealed collection, but you can do it with Python, or have to unseal the collection first?
It sounds already possible: so long as a collection (or an object) isn't linked to the scene, it doesn't appear in the scene's outliner.
To do this, you just have to Right 🖱️ > Unlink the collection from the outliner.
The collection and its content will still be in the file, but not in the scene (hence you see it in the outliner in Blender File mode which shows everything in the file, but not in View Layer mode which shows only the content of the current view layer or the current scene). And that, while its objects will still be able to interact with the scene (example above, the empty is used in a mirror modifier).
In your case the objects of the collection are not visible in the scene anymore. What I propose is that you can both still see the collection in the outliner, just not its children and have its content visible in the scene.