[marczellm]

I don't think Firefox will re-add built-in RSS support after removing it in 2018 (https://support.mozilla.org/en-US/kb/live-bookmarks), but the replacement addon whose development spun out of that deprecation is quite good. https://addons.mozilla.org/en-US/firefox/addon/livemarks/

For Feedly users I also recommend this addon: https://addons.mozilla.org/en-US/firefox/addon/feedly-notifi... It can be opened as a sidebar turning my browser into my feed reader.

[onli]

I'm of course also not certain of this. But live bookmarks might not be the goal that needs to be reached, the simple RSS icon when a site has a feed would already a big improvement.