This bookmarklet creates a markdown-style link for the current webpage

javascript:function htmlEscape(s){s=s.replace(/&/g,'&');s=s.replace(/>/g,'>');s=s.replace(/</g,'<');return s;} function linkEscape(s){s=s.replace(/&/g,'&');s=s.replace(/"/,'"');return s} h = '[' + htmlEscape(document.title) + ']' + '(' + linkEscape(location.href)  + ')'; with(window.open().document){write(h+'<form name=f><textarea  name=a rows=5 cols=80 wrap=hard>'+htmlEscape(h)+'</textarea></form>'); close(); f.a.select(); } void 0

It’s shamelessly ripped off from this bookmarklet which creates an html-style link for the current webpage

javascript:function htmlEscape(s){s=s.replace(/&/g,'&');s=s.replace(/>/g,'>');s=s.replace(/</g,'<');return s;} function linkEscape(s){s=s.replace(/&/g,'&');s=s.replace(/"/,'"');return s} h = '<a href="' + linkEscape(location.href) + '">' + htmlEscape(document.title) + '</a>'; with(window.open().document){write(h+'<form name=f><textarea  name=a rows=5 cols=80 wrap=hard>'+htmlEscape(h)+'</textarea></form>'); close(); f.a.select(); } void 0

I got the above, I think, from Web Development Bookmarklets

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