[solved] Custom "wait for change"

[gin]

Hi,

I want to search for a piece of text in firefox and do some stuff IF that text is found.

I tried using wait for change to no avail. Is there a function or a way to * almost * do the same thing? Here's how it would look like

1. get first screen shot within an area
2. find text
3. get second screen shot within an area
4. compare screen shots.
5. If 4 is different then do stuff.

I hope that makes sense. I'm definitely open to any solution that achieves the goal.