Seeking simple filter - delete HTML line containing string

[gpetty]

I'm a non-scripter who is hoping to find an existing greasemonkey script that does (or can be readily adapted to do) the following extremely simple task:

1) For a user-specified website (e.g., www.annoyingforum.com) , scan the source of the page to be displayed for any of a small set of user-specified strings (e.g., "posted by: idiot", "posted by: psycho", etc.).

2) Delete the entire line of HTML containing the offending string.

3) Display the remaining content in the usual way.

Thanks