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const grid = new Grid({
    ... Other configurations
    store : {
        sorters : [{
            fn : (recordA, recordB) => {
                const [store] = recordA.stores; // Get the store reference
                const { first } = store; // Get the first register of the store
                // If it's the first register, always put it in first place
                if (first.id === recordB.id) {
                    return 1;
                }
                // apply custom logic, for example:
                return recordA.name.localeCompare(recordB.name);
            }
        }]
    },