This addon was recommended as a way to prevent a user from deleting the history but it would seem it doesn't do that anymore. Additionally it would not unlock, even with the correct password, and I had to manually remove the addon to get access back to my settings.

configured to block installation of plugins, tried it and it still works to install plugins -> useless

Password screen freezes once you enter your pw. I thought I'd locked myself out... but actually you can remove it by clicking on the gear symbol next to the extension - which isn't of course something you should be able to do if the plugin worked as it should

As now FF 104.0.2 , this extension doesn't do anything useful...It doesn't block any downloads nor bookmarks

Downloads not exist but the worst is the password. If I use a password never open

it does lock ur add ons, but the password doesn't work so u are basically locked.... u can remove it tho in safe mode

Absolute junk, I should have read the 1 star reviews before installing. Firstly, does not prevent removing extensions by right clicking them on the toolbar and hitting remove. Most importantly, does not accept the password you set, making it impossible to access the add-ons page to change the settings for this extension or remove it if it's not in the toolbar.

The safemode guide by the developer DOES NOT WORK for removing this extension. I had to go to Firefox Menu>Help>Troubleshooting Mode in order to remove it.

As soon as I start Firefox with this add-on it keeps trying to make a TCP connection to static.237.48.201.138.clients.your-server.de:https (IP address --> 138.201.48.237) every minute.

Won't accept the password.

The password continue button is broken and it wont proceed to check the password and navigate to options. As a result the user can not access his/her options without having to access Firefox's safe mode and removing/disabling this extension. However you still have the ability to lock your settings as claimed...

Das Passwort wird nicht gespeichert, mehrfach versucht....neu Installiert aber geht leider nicht

doesn't accept the password to unlock

doesn't accept the password to unlock, makes it useless

The extension no longer accepts passwords. Most likely it has to do with new firefox update. You enter correct password and instead going to the page you intend(i.e. addons) you get password page again.
I'll also raise an issue on Github

Sadly, today july 29, 2020 firefox updated the browser and this add on is broken now miserable, it won't accept the password you set on new version of firefox :(

thank you