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Extensions 
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easyfundraising Donation Reminder
Never miss a donation for your charity or good cause again with the easyfundraising donation reminder
Quidco Cashback Reminder
The Quidco extension reminds you of the cashback you could be earning when browsing your favourite retailers.
Widilo Cashback Reminder
Get cashback in one click on all your purchases when you shop online with the Widilo Cashback Reminder
Water Reminder
Choose to have an audio, visual, or audio and visual reminder to take a drink, along with a wide audio selection.
FaniMani.pl Donation Reminder
Thanks to our Donation Reminder, on avareage 2.5% of your online shopping will be donated to the chosen NGO.
Give as you Live Donation Reminder
Give as you Live Online is the free way to raise funds for charity with your everyday online shopping.
HelpfreelyApp™ - Donation Reminder
Helpfreely.org - Users can generate funds for their favorite NGOs through online shopping, at no extra cost
Owl Reminder for Google Calendar™
Owl Reminder can connect your Google Calendar and provide desktop notification for events.
Compared with existing solutions it has…
Break Reminder
This is a simple app for setting up repeating notifications or reminders.
Perfect for reminding yourself of taking hourly breaks or…
The Last Sunday: reminder of life rushing by
Get reminded of how little of your life is left with each new tab!
Drink Water Reminder
Drink Water Reminder - This extension will help you to remind drink water in a periodic time interval. Stay Hydrated
Desk Yogi Reminder
Desk Yogi every day keeps desk butt away! This app reminds you to get up and move throughout the workday.
Goal Reminder
Reminds you of your goals in life while wasting your time in the internet. No registration. Full privacy. Speech (TTS)
Site Reminder
Add custom reminders at the top of any page or site, like 'don't forget this is the company's Twitter account.'
Bookmark Reminder
An extension that allows you to add a page as an event in Google Calendar or save as an .ics file, acting as a reminder
Better URL Reminder by PWS
A simple productive tool that reminds user to open the URL later (extremely useful, I swear). Update on 2016-09-05
Chrome AWS SAML Token Expiry Reminder
Re-authenticate with AWS federated ADFS (SAML) credentials when they expire.
We-Care Reminder
Turn purchases from your favorite online merchants into donations to your nonprofit, school, or association -- at no cost to you.