Loading states are shown during async setup operations

A submit button with no loading state invites double-clicks that create duplicate accounts, double-charge users, or race against each other to corrupt state. A post-signup redirect that shows a blank white screen for 1-2 seconds leaves the user wondering whether something broke and occasionally triggers a browser back button press that aborts the flow. The user-experience taxon flags both as foundational: any asynchronous operation without visible feedback degrades perceived reliability and invites user behavior that causes real bugs.

Disable submit buttons and swap their label while a submission is in flight, and add a loading.tsx file for any async route that can render blank on transition. Edit src/app/(auth)/signup/page.tsx to gate the button on an isPending flag, and create src/app/(auth)/loading.tsx with a spinner.

<Button type="submit" disabled={isPending} className="w-full h-11">
  {isPending ? 'Creating account...' : 'Create account'}
</Button>

• ID: saas-onboarding.activation.loading-states-during-setup

• Severity: low

• What to look for: Count all async operations in the onboarding flow: form submission, OAuth redirect, account creation API calls, initial data loading. For each, classify whether a loading state is rendered. Report the ratio of operations with loading states.

• Pass criteria: 100% of async operations during onboarding have a visible loading indicator. The submit button is disabled during form submission to prevent double-submissions. Any async data fetch has a skeleton or spinner. No blank screen exceeds 500ms without a loading indicator.

• Fail criteria: The signup form submit button remains active and shows no loading state during submission (allowing double-clicks that create duplicate accounts); the post-signup redirect shows a blank screen for more than 500ms with no loading indicator.

• Skip (N/A) when: No async operations exist in the onboarding flow (static site with no backend).

• Detail on fail: "Signup form submit button shows no loading state and remains clickable during submission. Post-OAuth redirect shows blank white screen for 1-2 seconds with no spinner or skeleton."

• Remediation: In your signup form at src/app/(auth)/signup/page.tsx:

  <Button type="submit" disabled={isPending} className="w-full h-11">
    {isPending ? 'Creating account...' : 'Create account'}
  </Button>
  

  For page transitions, add src/app/(auth)/loading.tsx with a spinner component.