I remember times of flashing effects on web, visit books on almost every private web, blinking clocks and Flash games. Internet in 2006 was full of Flash technology. Because of lack of current technologies, like HTML5 and WebGL, most effects was done by Flash. You had to install plugin from Adobe to run this content, so it was not native. I think that end of Flash began in 2007, when Steve Jobs introduced first iPhone and iPhone OS (later renamed to iOS) was said to never support Flash. And this iconic visionary from Apple was right.
Though Adobe announced that support for its Flash technology will end in 2020, Flash is already dead for many years. It was pretty funny to watch how one of Slovak banks was developing new Internetbanking via Flash technology. Internet really needed to get rid of this junk technology and thanks for initiation from Apple, Flash content (almost) dissapeared from Internet.
If you still have Flash content on your webpage, you should hurry. Not only because of ending support from Adobe, but Google will no longer index Flash content on webpages. Webpages will be indexed as before, but crawlers will ignore all Flash content, like Flash videos and Flash games.
All modern web browsers already block Flash. Before few years, I sometimes needed Flash, so I installed Google Chrome as secondary browser instead of installing Flash plugin into Safari. The main reason was that Flash plugin in Chrome ran in secured sandbox. Since I no longer need Flash and I have privacy issues with browser from Google, I replaced Chrome with Firefox.