Flash had a ton of vulnerabilities. It felt like one zero-day RCE per year.

Flash never had a good FOSS implementation until years after Flash Player was discontinued.

I was very happy about the death of Flash Player, but neutral on the death of the Flash format.

I didn't celebrate per se, but Flash was incredibly insecure and HTML5 was good enough for most of these simple games and it came out in... 2008, so 13 years before Flash went EOL.

What I did celebrate was finding out that Ruffle is a thing and most of your old favourite Flash games websites use it now so you can play your old favourites again! It's also open source and written in Rust so everything necessary to give the programmer nerd in me a boner.

I was a flash dev back then. People were very happy because of no more plugin need, no more badly scripted flash-ads that ate 100% cpu, etc.

Also Apple......

I was happy.