Well almost. For sometime now Adobe Flash has been a significant security risk for PC users. In fact, across other platforms too. In fact Apple has never allowed it on iOS, and can no longer get Flash for Android (unless you side-load an old version; BAD idea). Flash is being replaced by HTML5, and you should probably ditch Adobe Flash for good. Those websites still using Flash are re-tooling to ditch Flash, and those sites who aren’t should be.
YouTube historically has been a huge purveyor of Flash, but even YouTube is now giving you the option to use only HTML5 for displaying their videos. And I highly recommend you that.. and to also fully uninstall Flash from your computer, and to never look back. Really.