Studio: Ensure the scrollbar works correctly on onboarding screen

[katinthehatsite]

Related issues

• Fixes STU-453

Proposed Changes

This PR ensures that the scrollbar works correctly on the onboarding screen: when you are on a scrollbar, it should scroll:

Screen.Recording.2025-05-07.at.11.14.49.AM.mov

Testing Instructions

• Pull the changes from this branch
• Start the app with npm start
• Delete all Studio sites to see the onboarding screen or alternatively, apply this diff:

index c06b9cb..3224a7d 100644
--- a/src/components/app.tsx
+++ b/src/components/app.tsx
@@ -20,7 +20,7 @@ import { WhatsNewModal, useWhatsNew } from 'src/modules/whats-new';
 
 export default function App() {
        useLocalizationSupport();
-       const { needsOnboarding } = useOnboarding();
+       const { needsOnboarding } = { needsOnboarding: true }; //useOnboarding();
        const { isSidebarVisible, toggleSidebar } = useSidebarVisibility();
        const { showWhatsNew, closeWhatsNew } = useWhatsNew();

• Once on the onboarding screen, confirm that you can use the scrollbar as expected

Pre-merge Checklist

• Have you checked for TypeScript, React or other console errors?

[gavande1]

The changes are working as expected. Looks good to me! 👍

[katinthehatsite]

Thanks for review @gavande1 ❤️

One concern that I have is that this change makes the right side of the app not draggable on the onboarding screen which might not be obvious to the user (although they are usually exposed to this screen just briefly). That said, it is the simplest solution in my opinion. I spent some time dancing around the scrollbar but I could not find something that was straightforward to keep the scrollbar working and keep the app draggable from the right side. I tried to keep the top and bottom scrollable but it was making the app look strange with the scrollbar being cut off.

Before I go down more rabbit holes with this, @wojtekn are we okay with this tradeoff? Or do you think we should explore the solution further? Thank you

[wojtekn]

Seems to be okay.