Good addon but it's a pain for me to use Youtube. In about:addons under options I can only select "moderate". Is there another way to lower Youtube's strictness? I saw at the github's site within the wiki that you can edit the json file. And I did. But I can't seem to follow from there. Can you help me? What are the next steps if I don't have Linux? Or is it not possible to do this on Windows? I tried zipping the folder, renaming it to xpi and injecting it with Nightly by also removing something in about:config about addons being signed, but it didn't work cause it said the file was corrupt. Thank you for your time.

For some reason on my father's pc the only youtube choice is moderate. I have choices on other pc's so not sure what went wrong.

I do not recall ever installing this addon and it hijacked every YT link I clicked on like SafeMode was turned on.

Overall, a very good extension. Could you add https://www.onesearch.com/ to the list?
edit: I think I found the answer to your question. In the url of the search result, there is a vm parameter that can have 3 values. I found out that vm=r is strict, vm=i is moderate and vm=p is off.
I hope this helps you.
edit2: Added one star after onesearch was added. Thank you again.

Its a great idea but it does not seem to work very well?!? I installed this extension to include private mode, and nothing seemed to happen?!? I even went so far as to restarted Firefox and still nothing happened when I visited https://xhamster4.com/photos/gallery/12786417/324655470 as a test and nothing happened, am I missing something? I will update if this is resolved.

Thank You!

Thank you so much for this !!!

Thank you so much.....

Awesome! I love that I can still watch YouTube, but why do I have to choose "under 18" to allow restricted content? (moderate and strict block restricted videos)

This is very good, but it keeps forgetting the setting for YouTube leniency. I'm on Firefox 64 on Ubuntu.

It breaks qwantjunior.com on Firefox

Edit 2018/12/15 : No, it always qwantjunior.com on Firefox 60.4.0esr (V4.3.1)
Edit 2019/01/01 : It always breaks qwantjunior.com and qwant.com on Firefox 60.4.0esr (V4.3.2)

being able to disable certain sites from getting blocked, for example I don't want YT to get blocked. And reddit doesn't really work (can easily view everything after clicking yes I'm 18).

Great, especially when combined with another Add-on called "Public Fox", which allows adding password protection on the Add-ons menu to prevent disabling the Add-on.

Thank you so much for making this add-on. It is too easy to turn off safe search, and making it just a little harder is a great idea.

Merci pour cet excellent addon. Mais je dois le désactiver pour pouvoir lire les vidéos YouTube.
Thanks for this excellent addon. But I must disable it to play YouTube videos.

I really like this extension. It work very well. It enforce the strict mode on many search engines. An the user cannot change the strict mode. However, the extension should be password protected to block it's deactivation on a child account.