WebView2 creates at wrong size (possible regression?)

Description
It appears WebView2 always creates at the wrong size, and then quickly fires a resize event for the correct size.

Here's a Visual Studio project that demonstrates what happens:
resize-bug.zip

It's basically the Win32 getting started demo, but adapted to create a webview exactly 600x600, and then loads the following HTML string:

<h1>Hello world</h1>
<script>
console.log(`Startup window size: ${window.innerWidth} x ${window.innerHeight} @ ${performance.now()}`);

window.addEventListener("resize", () =>
{
	console.log(`Resize event: ${window.innerWidth} x ${window.innerHeight} @ ${performance.now()}`);
});
</script>

Using the debugger I verified that there is a call to put_Bounds sized exactly 600x600 prior to the call to NavigateToString to load that code. After building and running and viewing the console, it logs this:

Startup window size: 961 x 1032 @ 162.79999999981374
Resize event: 600 x 600 @ 175

Where did the size 961 x 1032 come from? It's always specified 600 x 600, but it seems it only gets the right size just after startup. It should have the correct size on startup and not fire a resize event.

This might seem fine but it's a hacky way to do things: suppose an app reads the window size immediately, then it runs some async init code, and then it attaches a window resize event. If it misses that very-soon resize event, it is left with the wrong size.

In our production app we see something even weirder but I can't reproduce it: we get a resize event for the size 961 x 1032 (i.e. the wrong size), but later on if we read the window innerWidth/innerHeight it returns the correct size. So it seems it fired a resize event with the wrong size, or it silently updated the size without firing a resize event, or since our code is pretty complicated, we just somehow fell victim to the kinda hacky way WebView2 handles resizes.

We've had the same code running for a year or two now and users only just reported this to us, so I suspect it's a regression in a recent WebView2 update.

Version
SDK: 1.0.1343.22
Runtime: stable 105.0.1343.27
Framework: Win32
OS: Observed on Windows 10 and Windows 11

AB#44174157