However, it's still possible to install Pulltube's Chrome extension.
It takes just a couple extra steps:
— download extension package here: Pulltube Chrome Extension
— unzip it and put the extracted folder somewhere safe, maybe Documents folder. It needs to stay there for Chrome to use a source, when using the extension.
— launch Chrome and go to Settings > Extensions or click this chrome://extensions
URL or copy paste it to the address bar.
— turn on Developer mode
then click Load unpacked.
— navigate to that location, where you saved extension folder, select it.