The Chrome Web Store—where you get Chrome browser extensions—is controlled by YouTube's owner Alphabet/Google. Even an extension ostensibly for this purpose—like the obviously named Video Downloader professional above—states right up front in its description, "The download of YouTube videos to hard drive is locked because of restrictions of the Chrome Store." In general with Chrome extensions, the download of any RTMP protocol video (protected videos) or streaming video isn't possible. 

On iPhones and iPads, you'd think there would be no such restriction since Apple and Google aren't exactly the best of pals. But on the few apps I tried in the first edition of this story, not only wouldn't they download from YouTube, they're not even available anymore. One of those apps said in its description, "downloading from YouTube is prohibited due to its Terms of Service." Apple is ensuring that app makers play by the rules—even Google's rules. All the better to get Google to block someone who eventually does something illegal with iTunes downloads.
Yet another alternative for downloading YouTube videos is Clip Converter. It is a free online media recorder application which will allow you to record, convert and download nearly any audio or video URL to common formats. In order to download a YouTube video, paste your YouTube URL at Video URL and press “Continue”. Then select the format and the options for conversion and press “Start”. Once the conversion is finished, you would be able to download the converted file.
Step 1:   Free download YouTube video downloader on Mac iMac Pro, Macbook Air/Pro or Mac Mini and install it, copy the URL of the video page. find a video you'd like to save offline, then paste the URL and click "analyze" to load the YouTube video details. Or click "paste & analyze" button to automatically detect the YouTube video opened in browse.
Do you prefer to avoid installing software? Video download helper sites do the download work for you, providing conversion and then a download link—you don't have to install anything on your PC. It can take a lot longer, depending on the size and quality of the video you want—a typical two-minute movie trailer in 1080p can be around 30MB—but you can't beat the convenience. 

YouTube allows you to watch, upload and share various videos including HD/4K content with users. It's said 500 hours of video are uploaded to the site per minute nowadays. However, YouTube only allows you to do such things when you connect to internet and YouTube doesn't allow 4K streaming in Safari. What could you do if you wanna save your HD videos on Mac or what if you are in a place, e.g. on a plane, where you cannot access to network? Hold on, we just gather up the top lists of free YouTube downloader for Mac software, browser extensions and online services targeted for Mac users to deal with downloads of YouTube videos on macOS freely.
You just install the downloaded software, and then you put the URL into the link and click to download. It’s that simple, and you’ll be able to get started listening and watching your favorite videos again in no time, and without having to get online again. That makes it great for when you’re traveling anywhere where you won’t have an internet connection for a long period of time. For those who haven’t used a YouTube channel downloader before, this one is going to make it super simple, and you’ll wonder why you haven’t done it before.
The next step is to open a command prompt by typing “cmd”  into the Windows search box and hitting enter. This opens up a command-line interface. Right-click in the command line interface box and hit ctrl-v to paste in the command. You’ll notice that the command is huge and unwieldy – that’s why we copied and pasted it from the browser interface, rather than typing it in from scratch.
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