Elementor: AJAX item picker for tags & widgets (large datasets)

When a Dynamic Tag or widget setting must point at one specific record out of many — "this product", "that landing page", "this author" — you need a searchable picker. On a small set a preloaded SELECT2 is fine. On a 20k-product store it is a trap: Elementor renders every option into the panel on load and the editor hangs. This skill is the AJAX-search alternative and how to degrade it when Elementor Pro is absent.

The misconception (and why the editor freezes)

"I'll list the products in a SELECT2 so the user can search them."

// ANTI-PATTERN at scale — every product becomes a preloaded <option>
$options = [];
foreach ( wc_get_products( [ 'limit' => -1 ] ) as $p ) {
    $options[ $p->get_id() ] = $p->get_name();   // <-- 20k entries in the panel
}
$this->add_control( 'product_id', [
    'type'    => \Elementor\Controls_Manager::SELECT2,
    'options' => $options,
] );