Bookmark Date Stamper by Marek Boháč

If you for example don't want to miss any article of a regularly visited news website of yours, you can use this extension to quickly (using a key combo) note when the last time you had read it through was.

Upon pressing the keyboard shortcut, this add-on will search all bookmarks for the URL of the current page. If found, it will display the title of the found bookmark and suggest a new title, containing the current date (and/or time). The user is given a possibility to edit it to taste, or just confirm the suggested one.

Usage:
After the page has loaded, press:
Ctrl + Alt + "+" (or click the add-on's toolbar button) to add both the date and time
Ctrl + Shift + "+" to add the date only