How to set up an Instant Action: Click
Navigate to Notifications > Add Notifications > All Notifications > Instant.
Select "New Action +"
Add the URL of the webpage of the button or link
Select: "Click"
Add the action element's CSS selector (see below)
Hit save and you're done!
How to find CSS selector
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In Chrome, right-click
on the element and select inspect
, hover over the HTML tags and find your desired element (it will be highlighted) in the source pane then (right-click) > Copy > Copy selector
.