SvelteKit restores removed or modified url hash after load function

Describe the bug

I am building a SvelteKit SPA app that is using Authorization Code Flow with PKCE with Keycloak.
I want to handle the auth redirect in the load() function of the root +layout.js file. During auth handling, Keycloak JS SDK removes the hash from the url. The problem is that SvelteKit restores the hash after load() function and the rendered url has the auth redirect hash visible.

See the repro below.

Reproduction

+layout.js

export const ssr = false;

/** @type {import('./$types').LayoutLoad} */
export async function load() {
	console.log('[+layout.js] before auth:', window.location.hash);
	await handleAuth();
	console.log('[+layout.js] after auth:', window.location.hash);
}

+page.svelte

<script>
	console.log('[+page.svelte] script:', window.location.hash);
</script>

<main>DEMO PAGE</main>

Screenshot (see the address bar and console logs):

Logs

No response

System Info

System:
    OS: macOS 12.4
    CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
    Memory: 440.96 MB / 32.00 GB
    Shell: 5.8.1 - /bin/zsh
  Binaries:
    Node: 18.11.0 - /usr/local/bin/node
    Yarn: 1.22.19 - /usr/local/bin/yarn
    npm: 8.19.2 - /usr/local/bin/npm
  Browsers:
    Chrome: 106.0.5249.119
    Firefox: 105.0.3
    Safari: 15.5
  npmPackages:
    @sveltejs/adapter-static: next => 1.0.0-next.44 
    @sveltejs/kit: next => 1.0.0-next.516 
    svelte: 3.51.0 => 3.51.0 
    vite: 3.1.8 => 3.1.8

Severity

serious, but I can work around it

Additional Information

No response

Start with the +layout.js load() reproduction and compare window.location.hash before and after handleAuth(), then inspect the navigation lifecycle that runs before +page.svelte. Reproduce the SPA case with the supplied SvelteKit/Vite setup and verify that a hash removed or changed during load() is not restored in the rendered URL.