Removal of UTF-8 charset on Form requests causes issues

[jonkjenn]

Sorry if I'm missing something very basic. It's a bit tricky to confirm that it's not just something weird about my setup.

There are servers that default to other encodings like ISO_8859_1 for application/x-www-urlencoded. This, #31781, seems like a breaking change towards these.

I think this is the case for standard Spring boot Tomcat applications. The default is ISO_8859_1. So this could break some standard Spring to Spring integrations.

Seems tricky to solve this on the server end unless you're certain that nobody depends on the default being ISO_8859_1.

Could it be that the new behavior should be opt-in? I have not even found a way to opt-out.