React Lazy Loading Causes Intermittent Crash in SPFx Web Part

[BJS1209]

Target SharePoint environment

SharePoint Online

What SharePoint development model, framework, SDK or API is this about?

💥 SharePoint Framework

Developer environment

None

What browser(s) / client(s) have you tested

• 💥 Internet Explorer
• 💥 Microsoft Edge
• 💥 Google Chrome
• 💥 FireFox
• 💥 Safari
• mobile (iOS/iPadOS)
• mobile (Android)
• not applicable
• other (enter in the "Additional environment details" area below)

Additional environment details

• browser version: Chrome (142.0.7444.176)
• SPFx version: 1.2.1
• Node.js version: 22.16.0

Describe the bug / error

Description:

I created a SharePoint Framework (SPFx) web part where I am using React lazy loading for components. During the initial loading of the SharePoint page containing the web part, the page crashes intermittently (approximately 4 out of 10 times). After refreshing the page, the web part loads and works perfectly fine.

Investigation:

While debugging using React DevTools, I observed that one of the SharePoint page components has a Suspense fallback set to null. This is causing the entire page to suspend and results in a crash during the first load.
There is no error in console.

Steps to reproduce

1. Load the SharePoint page with the SPFx web part containing lazy loaded React components.
2. The page crashes randomly on initial load.
3. Refresh the page, and the web part loads successfully without errors.

Expected behavior

The SPFx web part should load reliably on the first attempt without crashing, even if React lazy loading is used.

[Ashlesha-MSFT]

Hello @BJS1209,
Thank you for bringing this issue to our attention. We will look into it and get back to you shortly.
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