With the latest introduction of multiple columns, each group (or pipeline in GoCD) was shown in a separate row.
If you were using pipelines with only one stage, this wasn’t the most effective way to visualize that.
There is now a new option to “collapse groups” so more than one can be displayed in one row.
This setting only makes a difference if you are using the “fixed” layout.
As you can see on the screenshots below, two groups (Order Entry UI and Javadocs) are shown in one row if there is enough space.