Does not work in calendar.google.com

[mems]

Does not work in calendar.google.com

[mems]

If you don't see the popup, it's because your browser popup blocker is active. A bookmarklet (or any other page scripts) can't open a popup without be executed by a user click in the page, else otherwise the popup will be blocked. Sadly this extension can't do anything for that

I clean up a bit the bookmarlet for intelligibility (remove comments and spaces) and fix the URL of Google calendar (for the event title part) and it works (if you click on blocked popup in the Yellow bar of Firefox):

javascript:var%20s;if(window.getSelection){s=window.getSelection();}else%20if(document.getSelection){s=document.getSelection();}else{s=document.selection.createRange().text;}if(s==''){prompt('QuickAdd');}var%20re=RegExp('[AaPp][Mm]');if%20(encodeURIComponent(s).match(re)){}else{var%20d=new%20Date();var%20hr=d.getHours();var%20min=d.getMinutes();if%20(min<10){min="0"+min;}s=s+"%20"+hr+":"+min;}void(window.open(encodeURI('https://www.google.com/calendar/event?text='+s+'&action=TEMPLATE&pprop=HowCreated:QUICKADD'),'addwindow','status=no,toolbar=no,width=520,height=470,resizable=yes'));

If you need to open the popup without been blocked, you need to rewrite this bookmarklet to show a button instead, then you could click on it to open the popup each time you use the bookmarklet