Multiple Select Splitter

For multi select with more script options. If you want to select more options, you must hold CTRL key. (default select behaviour)

Check out Github

Simple select, no mutiple
Multiple select of size 7 with group counter. Second select is cleared, when first changed.
Multiple select with group counter. You can select maximum 2 options of all categories.
Multiple select with group counter. You can select maximum 3 options ONLY from one category.
DashboardKit Customizer
Header settings

Sidebar settings

Layout settings