Incorrect Callback/404

[Pukimaa]

Hey. Whenever I try to log in this flow happens:
Login -> Discord Oauth Flow -> Success Page -> Redirect to Tauri -> Callback to localhost:1420/404

Meaning everything stays in the same page and no refresh is forced, thus my application not recognizing the logged in state. However once I force a reload or restart my application, everything works as expected. It's just the last callback.
I followed the Svelte Setup Guide from the README.md 1:1 while replacing the schema etc.

Logs

Browser Logs:

[Log] [Better Auth Tauri] handleAuthDeepLink fetch – "/callback/discord?callbackURL=%2F&code=LNhnvcQ0cVqJ9NKhmGQdeS4nk1lu1z&state=wplr2W88dpjoNiKVlFgx2xXXAeg143ds" (@daveyplate_better-auth-tauri.js, line 2760)
[Log] Auth request: – "/callback/discord?callbackURL=%2F&code=LNhnvcQ0cVqJ9NKhmGQdeS4nk1lu1z&state=wplr2W88dpjoNiKVlFgx2xXXAeg143ds" (+layout.svelte, line 33)
[Error] Failed to load resource: the server responded with a status of 404 (Not Found) (localhost, line 0)
[Log] [Better Auth Tauri] handleAuthDeepLink response (2) (@daveyplate_better-auth-tauri.js, line 2765)
{data: null, error: {status: 404, statusText: "Not Found"}}
"/callback/discord?callbackURL=%2F&code=LNhnvcQ0cVqJ9NKhmGQdeS4nk1lu1z&state=wplr2W88dpjoNiKVlFgx2xXXAeg143ds"
[Error] [Better Auth Tauri] handleAuthDeepLink error (2)
{status: 404, statusText: "Not Found"}
"/callback/discord?callbackURL=%2F&code=LNhnvcQ0cVqJ9NKhmGQdeS4nk1lu1z&state=wplr2W88dpjoNiKVlFgx2xXXAeg143ds"
	handleAuthDeepLink (@daveyplate_better-auth-tauri.js:2773)
[Error] Auth error: – {status: 404, statusText: "Not Found"}
	onError (+layout.svelte:42)
	handleAuthDeepLink (@daveyplate_better-auth-tauri.js:2779)

API Logs:

Started development server: http://localhost:3000
  api:dev | [Better Auth Tauri] Request URL: http://localhost:3000/auth/sign-in/social User Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/60.5 Safari/605.1.15 Host: localhost:3000 Pathname: /api/auth/sign-in/social
  api:dev | [Better Auth Tauri] Appending callback URL to social provider discord http://localhost:3000/auth/callback/discord?callbackURL=elysium://
  api:dev | [Better Auth Tauri] Callback URL: null /api/auth/sign-in/social
  api:dev | [Better Auth Tauri] Request URL: http://localhost:3000/auth/callback/discord?callbackURL=elysium%3A%2F%2F&code=LNhnvcQ0cVqJ9NKhmGQdeS4nk1lu1z&state=wplr2W88dpjoNiKVlFgx2xXXAeg143ds User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:145.0) Gecko/20100101 Firefox/145.0 Host: localhost:3000 Pathname: /api/auth/callback/discord
  api:dev | [Better Auth Tauri] Callback URL: elysium:// /api/auth/callback/discord
  api:dev | [Better Auth Tauri] Redirecting to: elysium://api/auth/callback/discord?callbackURL=%2F&code=LNhnvcQ0cVqJ9NKhmGQdeS4nk1lu1z&state=wplr2W88dpjoNiKVlFgx2xXXAeg143ds /api/auth/callback/discord
  api:dev | [Better Auth Tauri] Request URL: http://localhost:3000/auth/callback/discord?callbackURL=%2F&code=LNhnvcQ0cVqJ9NKhmGQdeS4nk1lu1z&state=wplr2W88dpjoNiKVlFgx2xXXAeg143ds User Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/60.5 Safari/605.1.15 Host: localhost:3000 Pathname: /api/auth/callback/discord
  api:dev | [Better Auth Tauri] Callback URL: / /api/auth/callback/discord

Video Walkthrough

2025-12-16.14-47-59.mp4