There are still some apps/programs that require Flash - catch-up tv for example. I use Firefox and I can set it so that it has to ask permission to activate as and when needed. Is this what you mean by warnings or are you talking about notifications to keep it up to date?
for a long time now the people who make shockwave have admitted it is a security risk and even recommend you stop using it. when i open the edge i get a message to say it has been disabled but you do have the option to click the bubble and use it but ..... NOT RECOMMENDED.