Ubuntu Unity GUI
Unity is a new desktop introduced in Ubuntu around 2012.
It made a significant change from the traditional desktop. Many operations has become “smart”. They also use much more memory and CPU. Often have fancy visual effects such as transparency, animation, etc.
The “smart” behavior is great for beginner. But for advanced users, it is unpredicable and annoying. So, switch to xfce or lxde.
If you have a question, put $5 at patreon and message me.