telegramShare.js

function telegramShare(url, text) {
    var tg = new URL('https://telegram.me/share/url');

    url = new URL(url);
    url.searchParams.append('utm_source', 'telegram.org');
    url.searchParams.append('utm_medium', 'share_telegram');
    url.searchParams.append('utm_campaign', 'share');

    tg.searchParams.append('url', url);
    tg.searchParams.append('text', text || 'Канал Финагина: @FinChannel');

    return '' + tg;
}