Works grate but there is an issue, as it does not allow the Thumbnail Tooltip to be displayed on Mouse over the Progress Bar, it only displays the Time Tooltip. I do not know if it happens when the extension's Mouse Control is ON or the Clean Player > "ProgressBar Heatmap" is checked to be removed, but when I disable the addon, the preview Thumbnail is displayed as it should.

When trying to check what is wrong, I found out that somehow the ".ytp-tooltip-bg" element can not load its properties and especially its "background" property.

Update: It seems to be a conflict between your extension and the Adblock Plus extension, cause when I disable one of them the Tooltip Thumbnail is displayed as it should, but when both extensions are enabled the Tooltip is not displayed. Notice that I have not enable any Ad options in Tweaks for YouTube. The problem exists even with your addon's default options.

After using another tool for YouTube for years, which is no longer being developed, I looked at various alternatives. This one was the best alternative that I liked the most. The only thing that really bothers me is the confusing layout of the settings. Everything is just all over the place. That's neither clear nor user-friendly! That should be made clearer. Apparently the developer has never heard of UI design! ;-) But otherwise, it has almost everything you need. Oh yes... and why can't one block "Member Videos"?
Edit:
I have this enabled, "Member Videos" in the sidebar are not blocked.

Working as expected but too complicated for me. Still use this instead of Enhancer for Youtube on Firefox.

This is amazing. Would give 5 stars, just need ability to resize Default player view, I want to make it smaller.

The best youtube extension that I have used, thank you for making it! I do have one issue however, Is it possible to get rid of the empty space in the first row of thumbnails? I have just two (sometimes three) thumbnails and then black space while the other rows show the correct amount. I have custom rich grid layout enabled with 6 items per row.

Really nice extension just wish it had an option to have an icon for audio boost, screenshot, and playlist autoplay. Also wish it had an option to both save screenshot and copy to clipboard with one action.
Another thing I just noticed is that audio boost is global. It's only useful for me if it is per video.

The extension is good, but needs some changes for the 5 stars. Changes such as adding audio boost icon, screenshot icon, cinema mode icon, etc. to player controls and not having to use keyboard shortcuts such as other extensions such as "Enhancer for YouTube."

Wish there was a more direct way of submitting feedback to know if an issue has been identified or sent before. Only support is email, and I haven't gotten back to yet after a few weeks. Apparently general support is a perk of the paid Patreon tiers, that's... weird.
All this to say the Playlist Duration is hidden on YouTube's playlist pages after a recent UI update. Sucks to have to request a fix like this in an extension review, but I legit don't know where else to take this. (Not spending $1 just to say "feature broke, plz fix")
My qualms with lack of support and the code not being open-source aside, this works much better than "Improve YouTube!" imo. (Better not let the dev for that hear this, or they'll get real mad)

Take a video snapshot (copy to clipboard) does not work. It says it copied to the clipboard, but it doesn't.

"Show playlist duration" doesn´t work any more....nothing is shown there in the playlist since 1 or 2 days.
Is there a chance this ius becoming fixed?

Would be really great :-)

it works great, but it would be nice if there was an option to add features such as fast forward or rewind by an amount of time of your choosing and have those buttons be present under the progress bar next to the volume button or something similar to what Rumble provides normally.

add option to completely hide thumbnails, if possible

Very high performance, but when using this extension in Firefox, there is a flaw that the function gets cut off in the middle of the function.

Most of the stuff works "fine" on Firefox, but just a few days ago, its stopped switching to cinema mode entierly. Just refuses to work. Most other options still do, just this one option...

Very nice extension is very configurable. The only thing missing for complete happiness is the automatic translation of subtitles into the language of your choice (autogenerated too).

It's good but the fact that you can't use double click as an input or just use the default interaction youtube interaction as a preset makes it some aspects of it worse to use than youtubes' default rather than better.