I recently switched to an RSS reader that supports its own read later service and while I wanted to completely transition, the new software didn't supply a similar "Save to X" Chromium-based extension. Kronos is a simple attempt to replicate that functionality while also playing around with building an extension.

After installing in your browser, clicking open the extension popup lets you assign a base URI to send articles to (e.g., "shortcuts://run-shortcut", "mailto:<>", etc.).

Once an address is assigned, selecting the popup will send the current tab, while subsequent clicks will reopen the configuration menu. The banner title can be clicked to view a cache of recently saved articles.