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Click on the bell icon to be taken to your to do list.
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Fill in a response
Each of the entries in this list is a quick link to the event on your timeline. You can respond to the invitation in two ways:
Clicking on the name of the to do, which will take you to a full page view of the event for you to fill in.
Clicking on the preview icon which will open the event in a popup window.
From there you can fill in your response and submit without leaving your position on the page.
As soon as you fill in and then submit that section the task will disappear from your to do list.
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