Александр

Поэтому arr.splice(index, 1)

-axios.post(baseUrlPost, {
+axios.post(baseUrlPost, formData, {
-   method: 'post',
-   body: formData,
    headers: { 'Token': this.token, },
})

https://axios-http.com/docs/post_example
https://axios-http.com/docs/req_config

document.querySelector('.bx-soa-customer > .bx-soa-customer-field:last-child')?.classList.add('xyz');

document.querySelectorAll('.count-wrapper').forEach((wrapper) => {
    const minusButton = wrapper.querySelector('.count-minus');
    const plusButton = wrapper.querySelector('.count-plus');
    const counterElement = wrapper.querySelector('.counter');

    if (!minusButton || !plusButton || !counterElement) {
        return;
    }

    let counter = Number(counterElement.textContent.trim()) || 0;

    minusButton.addEventListener('click', (event) => {
        event.preventDefault();
        if (counter > 0) {
            counter--;
        }
        counterElement.textContent = counter;
    });

    plusButton.addEventListener('click', (event) => {
        event.preventDefault();
        counter++;
        counterElement.textContent = counter;
    });
});

const string = '100 EUR * 10 +100 EUR - 300 EUR* 50 EUR';
const anotherString = string.replace(/\s*([-+/*])\s*/g, (match, char) => ` ${char} `);

console.log(anotherString);

Например так:

const makeTree = (root) => {
    const tree = {};

    const step = (root, branch) => {
        root.querySelectorAll(':scope > [class^="block"]').forEach((element, index) => {
            const className = [...element.classList.values()].find(
                (className) => className.startsWith('block')
            ) ?? element.className;
            const key = `${className}_${index + 1}`;

            branch[key] = {};

            const control = element.querySelector(':scope > input');
            if (control) {
                branch[key].value = control.value;
            }

            step(element, branch[key]);
        });
    };

    step(root, tree);

    return tree;
};

const tree = makeTree(document.body);
console.log(tree);

или так

const makeTree = (root) => {
    const tree = {};

    const step = (root, branch) => {
        root.querySelectorAll(':scope > [class^="block"]').forEach((element, index) => {
            const className = [...element.classList.values()].find(
                (className) => className.startsWith('block')
            ) ?? element.className;
            const key = `${className}_${index + 1}`;

            const controls = element.querySelectorAll(':scope > input');
            branch[key] = {
                values: [...controls].reduce((acc, control) => {
                    if (control.id) {
                        acc[control.id] = control.value;
                    }

                    return acc;
                }, {})
            };

            step(element, branch[key]);
        });
    };

    step(root, tree);

    return tree;
};

const tree = makeTree(document.body);
console.log(tree);

const pages = Array.from({ length: Math.ceil(reposCount / elementsCount) }, (_, i) => i + 1);

или

const pages = new Array(Math.ceil(reposCount / elementsCount)).fill(null).map((_, i) => i + 1);

или

function* range(from, to) {
    for (let i = from; i <= to; i++) {
        yield i;
    }
}

const pages = [...range(1, Math.ceil(reposCount / elementsCount))];

encodeURIComponent(
    decodeURIComponent('test+%0D%0Atest.+%0D%0ADtestestestes%0D%0Atesgdsger%0D%0A')
        .replace(/\+?\r\n/g, '+\r\n')
)

Во-первых, работаете в блокноте а не в редакторе кода?
if (${data.title} != 'null') такое вообще работать не будет.
Во-вторых, где пример ответа? Если уверены что в ответе именно null, то можно решить проблему так:

moviesEl.textContent = data.title ?? 'Another title';

cloneNode не копирует события, о чём написано в документации.

window.addEventListener('click', (event) => {
  event.target.closest('.element__button')?.classList.toggle('element__button_active');
});

Делегирование событий

e.target.dataset.name.replace(/^name-category_?/i, '')

arr.map((item) => ({ ...item, averagePrice: item.finance / item.physicalVolume }));