WebRequest для соединения с API Википедии

/** {string} URL queries in string */
let urlQueriesString = window.location.search,
/** {string[]} URL queries in array */
	urlQueriesArray = urlQueriesString.substring(1).split('&'),
/** {Object.<string, string>} URL queries in object */
	urlQueries = {},
/** {string[]} List of search keywords */
	searchKeywords = [],
/** {HTMLElement[]} List of <li> which will be inserted into DOM */
    liElements;

// Fills in urlQueries object
for (let i in urlQueriesArray) {
	urlQueriesArray[i] = urlQueriesArray[i].split('=');
    
    urlQueries[urlQueriesArray[i][0]] = urlQueriesArray[i][1];
}

// Gets search keywords from _sft_category parameter
searchKeywords = urlQueries._sft_category.split('+'); // or .split(' ')

// Inserts a <li> in the DOM for each keyword
for (let i in searchKeywords) {
	let ul = document.getElementsByTagName('ul')[0],
        html = `<li>${searchKeywords[i]}</li>`;
    
    ul.innerHTML += html;
}

// Gets inserted <li>
liElements = document.getElementsByTagName('li');

// Adds an event on click for each <li>
for (let i in liElements) {
    let li = liElements[i];
    
    // Checks instance type because last element of liElements is the length and we don't want to do what's following for this one
    if (li instanceof HTMLElement) {
    	// Creates new URL on click
        li.addEventListener('click', function() {
            let url = window.location.hostname + window.location.pathname,
                keyword = this.innerText;
                
            searchKeywords = searchKeywords.filter((kw) => (kw !== keyword));
            
            url += urlQueriesString.replace(/_sft_category=[\w\d_+-]+/, `_sft_category=${searchKeywords.join('+')}`);
            
            console.log(url);
            
            // Uncomment next line for reload with new url
            // window.location.href = url;
        });
    }
}

<ul></ul>