More columns in GNOME 3 app menu
You may use a GNOME Shell extension called "More columns in applications view".
This extension lets you
Set the number of columns in the "applications" view (by default, the maximum is only 6)
Another similar extension is "Application View Columns" (officially supports GNOME Shell version 3.30 currently). It lets you
Set the number of columns in the Applications Overview. Controlled by a slider in the system menu with a switch for increasing compactness for up to 12 columns.
