Open the Share menu on a record and go to the Groups tab to see this: you have to type in the exact identifier of a group to pull it up in the UI. Typing the description or a part of the ID is not enough. This is very inconvenient behavior, bad enough to make groups essentially unusable.
I'm not sure if we can fix this in our instance or if it needs to be fixed upstream. I would prefer to fix upstream rather than override a react component.