Works really well (and includes the video transcript in the search). Switched to it after the YCS addon stopped working consistently.

To the dev I would suggest renaming the addon so it's easier to find and so it stands out more in the results (searching for "youtube search comments" here returns it as the 15th option, below several irrelevant results)

edit: one minor issue is that it keeps reloading comments (in its database) every once in a while when scrolling the page, even after pressing stop