CSS Selector help

Using Chrome, simply right-click on the element you want to 'watch', then select inspect, you will then get the inspector window open.

What is a CSS Selector? Please read https://developer.mozilla.org/en-US/docs/Learn/CSS/Building_blocks/Selectors

right-click again on the HTML element source (the HTML code of the element you right-clicked on in the previous step will be selected alright), then you'll see another menu where you can copy the element selector to the clipboard.

For example - I want to get the selector for the "currently unavailable" text of an amazon product page

Then simply paste in the selector to the filter box in changedetection.io