jellyfin-web/src/elements/emby-programcell/emby-programcell.js

define([], function() {
    'use strict';

    var ProgramCellPrototype = Object.create(HTMLButtonElement.prototype);

    ProgramCellPrototype.detachedCallback = function () {
        this.posLeft = null;
        this.posWidth = null;
        this.guideProgramName = null;
    };

    document.registerElement('emby-programcell', {
        prototype: ProgramCellPrototype,
        extends: 'button'
    });
});