Does not work on old.reddit.com subreddits that feature sponsored posts.

[UramboTauro]

When using the classic version of reddit, old.reddit.com (which I often do, because the www.reddit.com redesign sucks), any subreddits that feature sponsored/promoted posts will prevent RLO from opening new tabs.

Seems to be just that particular combination. When a subreddit features user-generated content ONLY, (no promoted posts), the extension will work, even on classic old.reddit.com. And if you're on the redesigned www.reddit.com, RLO will work regardless of whether or not there is sponsored content among the posts. But nothing happens when you try to use the extension while browsing an old.reddit.com subreddit with sponsored/promoted posts.