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)

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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.
Nextro Customizer
Header settings

Sidebar settings