Google chrome extention

Not sure what is possible.

The most basic concept is:
– select the 1 pdf file on a webpage
– extract data from the pdf
– display results based on arguments of the extracted pdf data.

Example:
A site has a pdf with the word “apple” insite of it.
My preset argument was that if a pdf contains an apple, I want the text “Food” to display. So food displays in an overlay