Boring RSS by Tom

Boring RSS is a low-permission Web Extension that displays a toolbar button that searches the current page for RSS/Atom feeds.

Features:

• It's just a button.
• No special permissions: this only uses activeTab, rather than "Access your data for all websites".
• No options.

FAQ
Why does the RSS icon always show, even on pages that have no RSS feed?
Boring RSS could choose to only show if the page contained an RSS feed, but to do so would require "Access to all your data for all sites", because that's the permission needed to be able to inspect every page. This extension's reason-for-existence is to avoid that permission. If you're willing to provide that permission, consider Awesome RSS.