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If the survey does not have the location field, you can edit the survey and add the standard Location field to it
While posting a Timeline Update
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Launch the Quick Update popup
To do it from the Homepage, click the “+” symbol next to the tracker you want to post an update about
To do it from a Progress Board, press the “+” symbol in the card of the tracker you want to post an update about
The Quick Update popup appears for that tracker
In the Quick Update popup, click the Location symbol
The location text box appears
Enter the address where the story took place
Potential addresses will appear as you start to type
Select the correct address
Press Publish