Reddix - Reddit bookmarks by Vitaly Yerofeyevsky

Reddix helps you manage and search your Reddit saved and upvoted content.

Features:

• Save and organize your Reddit posts and comments in your browser's local storage.
• Search, sort and organize saved content using tags.
• Dark and light themes.
• View your content in a toolbar pop-up window or on a separate page.
• Import or export your data.

Please note that Reddit limits the number of posts you can fetch to 1,000. If you want to download more, please refer to the extensions help page for instructions on how to manually import all your content.

Source code:
https://github.com/flytaly/reddix-extension