However since 3.6, the when changing the value of a select box the change is saved directly to the system. I consider this very bad UI.

The root issue here is the size of the asset data and inherently the data structure of the assets table. Changing to an AJAX process got around a boatload of memory issues when you have large numbers of groups and permissions. So without some major core architecture work, the only fix here is some kind of notice indicating changes from the ACL widget apply immediately.

@roland-d tagging you as its kind of related to the component options we've been talking about

@Hackwar Do you have any suggestions on how you want it changed other than it needs to be changed? Besides the memory issues we also have issues with the max_input_vars not being big enough.

We are discussing a different setup of the global configurations in issue #31495

max_input_vars will be the end of me

Actually, I think it would be worth considering to move the whole access management out of the global configuration and into its own dedicated view. There we could define new behavior and maybe create something like a staging area, storing the changed settings in session first and calculating based on those, before commiting that to the assets table.