I am working with telegram on windows and its online version on web.telegram.org, when I share a link with my friend Telegram shows the icon or logo of some websites in that message:
Image
The first website is vajehyab.com and it has a favicon too (But do not showing that website icon), and the second is Stackoverflow and as you see the logo of stackoverflow and a litle description shows beside it.
Does websites do something or having some metadata that allow Telegram to access their logo, or it is an static program form Telegram programmers and the set some famous websites logo?
{var%20f='http://v.t.sina.com.cn/share/share.php?appkey=1515056452',u=z||d.location,p=['&url=',e(u),'&title=',e(t||d.title),'&source=',e(r),'&sourceUrl=',e(l),'&content=',c||'gb2312','&pic=',e(p||'')].join('');function%20a(){if(!window.open([f,p].join(''),'mb',['toolbar=0,status=0,resizable=1,width=440,height=430,left=',(s.width-440)/2,',top=',(s.height-430)/2].join('')))u.href=[f,p].join('');};if(/Firefox/.test(navigator.userAgent))setTimeout(a,0);else%20a();})(screen,document,encodeURIComponent,'','','https://img.manongdao.com/sparkler-677774__340.jpg', '推荐 相关推荐>> 的文章《How does telegram shows the Icon of some websites?》','https://www.manongdao.com/article-580505.html','页面编码gb2312|utf-8默认gb2312'));){kind=link}