Red-It от AugustoFrade

Red-It is a Firefox extension designed to enhance the your Reddit browsing experience by allowing you to block unwanted posts based on keywords. Take control of your Reddit feed and filter out posts that contain specific words, phrases and simple patterns you'd rather not see.

Recover your sanity while browsing today!

Features:
- General
- Block posts with a blocklist. Accepts wildcard (*)
- Block Communities
- Block Comments
- Block NSFW posts
- Block premium ads

Extension data management options can be found in the settings page.

Below are the following permissions the extension requires and what they are used for:

• Storage: saving and retrieving user-defined rules to block content with.
• Tabs: opening settings page and displaying blocked subreddit page.
• WebRequest, WebRequestBlocking: detecting subreddit access to deny access to it in case the subreddit is set by the user to be blocked by the extension.