Programming and/or add-on questions

Questions

1. Is there an add-on that allows me to do the following?
2. What's a very easy way to do the following via programming? js or whatever.

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I want to delete or hide a HTML section that has specific text. Using regex on the source HTML is quick, dirty, and ugly but is there another very easy way? There isn't - is there?

The thumb is an example. I want the Christmas shit gone.

So - if \b(Christmas)\b is in a TR then hide or delete it.

Quick/dirty is key. And I don't want to spend untold hours trying to learn and then failing to learn how to programmatically do it the right way. I know regex can be a nightmare but I want to do be able to do the removal/hiding at other sites too.

I don't see another way to reuse this method on any site. [Edit: That was confusing.]