accounts-frontend/src/services/loader.js

// On page initialization loader is already visible, so initial value is 1
let stack = 1;

export default {
    show() {
        if (++stack !== 1) {
            document.getElementById('loader').classList.add('is-active');
        }
    },

    hide() {
        if (--stack === 0) {
            document.getElementById('loader').classList.remove('is-active');
        }
    }
};