Unable to use arbitrary attributes

[groundedsage]

So this has been around for a while and has meant I have had to use dangerously setting inner html.

I use netlify and when doing form handling I need to be able to set an element attribute to netlify.
"netlify" true does not work for this. There is also other bits of code on the web which works this way so it would be handy if this could somehow be supported.

UPDATE: Rum handles this serverside when generating the static html as it uses Clojure. However it doesn't do custom attributes on the client side.

[groundedsage]

Referencing some links shared in the discussion in slack. All links were shared by misha personally haven't had time to review them. Just ensuring it is here as a reference.

Allow custom (nonstandard) attributes (REACT ISSUE). facebook/react#140

https://github.com/facebook/react/blob/b1b4a2fb252f26fe10d29ba60d85ff89a85ff3ec/src/renderers/dom/shared/ARIADOMPropertyConfig.js

https://github.com/facebook/react/blob/b1b4a2fb252f26fe10d29ba60d85ff89a85ff3ec/src/renderers/dom/shared/ReactDOMInjection.js#L63-L65

https://github.com/facebook/react/blob/b1b4a2fb252f26fe10d29ba60d85ff89a85ff3ec/src/renderers/dom/shared/DOMProperty.js#L40-L42

DOMProperty.injectDOMPropertyConfig({
  Properties: { amp: DOMProperty.MUST_USE_ATTRIBUTE },
  isCustomAttribute: attributeName => attributeName.startsWith('amp-')
})

https://github.com/facebook/react/blob/b1b4a2fb252f26fe10d29ba60d85ff89a85ff3ec/src/renderers/dom/shared/SVGDOMPropertyConfig.js#L295-L300