javascript:(function(){var keyword=prompt("For: NRW SHIPPING\nSite: http://www.mrw.es\n\nType your tracking number!","");var form=document.createElement('form');form.setAttribute('action','https://mrw.es/seguimiento_envios/validar_seguiment.asp');form.setAttribute('method','POST');var mrwFinderFollowCode=document.createElement('input');mrwFinderFollowCode.setAttribute('type','hidden');mrwFinderFollowCode.setAttribute('name','mrw-finder-follow-code');mrwFinderFollowCode.value=keyword;form.appendChild(mrwFinderFollowCode);var ojectCodeInput=document.createElement('input');ojectCodeInput.setAttribute('type','hidden');ojectCodeInput.setAttribute('name','OjectCodeInput');ojectCodeInput.value=keyword;form.appendChild(ojectCodeInput);var searchInput=document.createElement('input');searchInput.setAttribute('type','hidden');searchInput.setAttribute('name','SearchInput');searchInput.value=keyword;form.appendChild(searchInput);var isFromPublicArea=document.createElement('input');isFromPublicArea.setAttribute('type','hidden');isFromPublicArea.setAttribute('name','IsFromPublicArea');isFromPublicArea.value='true';form.appendChild(isFromPublicArea);var submitBtn=document.createElement('input');submitBtn.setAttribute('type','submit');submitBtn.setAttribute('value','Tracking...');form.appendChild(submitBtn);document.body.appendChild(form);setTimeout(function(){form.submit();},1000);})();

Save the code as a bookmark on your favorites to have this feature directly on your browser.