I have this really simple problem I can't seem to figure out. I'm trying to use JavaScriptKit to create an element in the browsers DOM and set some CSS style on it:

import JavaScriptKit

let document = JSObject.global.document

var spanElem = document.createElement("span")
spanElem.innerText = "hello"
spanElem.style.backgroundColor = "yellow"

_ = document.body.appendChild(spanElem)

But it seems that the assignment to spanElem.style.backgroundColor doesn't have any effect. When I run this code (as main.swift), the <span> is created but its CSS style is unchanged. Reading style.backgroundColor from the browser console also shows nothing, but changing it from there works as expected:

document.getElementsByTagName('span')[0].style.backgroundColor
""
document.getElementsByTagName('span')[0].style.backgroundColor = "yellow"
"yellow"
document.getElementsByTagName('span')[0].style.backgroundColor
"yellow"

I'm using carton 0.10.0, Swift swift-wasm-5.3.1-RELEASE, JavaScriptKit 0.10.1 and am testing with newest Chrome and Safari (with same results) on macOS 10.15.7.

What am I doing wrong here?