Prior to 575, AutomaticSize did not include the AbsoluteSize of GuiObjects whose Visible property is set to false.
Now that it does, it breaks any use case where any GuiObject which may be made invisible constrains the size of it’s containing automatically sized parent GuiObject, even when invisible. This makes AutomaticSize useless, since the flexibility of the layout becomes restricted, regardless of visible state.
No, it’s been including invisible objects for a while now. I’ve only seen it happen when it’s a descendant of a frame with AutomaticSize, not a child. I’ll try to send my own reproduction file later, I can’t right now.