SharePoint
SPFx webpart cannot be added to the local workbench
Target SharePoint environment
SharePoint Online
What SharePoint development model, framework, SDK or API is this about?
💥 SharePoint Framework
Developer environment
Windows
What browser(s) / client(s) have you tested
- [ ] 💥 Internet Explorer
- [x] 💥 Microsoft Edge
- [x] 💥 Google Chrome
- [x] 💥 FireFox
- [ ] 💥 Safari
- [ ] mobile (iOS/iPadOS)
- [ ] mobile (Android)
- [ ] not applicable
- [ ] other (enter in the "Additional environment details" area below)
Additional environment details
- browser version; latest
- SPFx version: 1.18.2
Describe the bug / error
It started on 02.10.2025 (last week), the local workbench page (/_layouts/15/workbench.aspx) does not work properly. 'Add a new web part' (+) button does not appear, just a button for adding sections.
And sometimes I can see the adding webpart button, but this time I cannot select the local or any webparts, even appear in the webpart list.
I can call 'manifests.js', but there is no workbench.html.
Steps to reproduce
- gulp serve
Expected behavior
I can create a package and deploy, it works properly, But, cannot test and debug SPFx webparts locally.
Hello @MSF-SP-Yasar,
Thank you for bringing this issue to our attention. We will look into it and get back to you shortly.
If you don’t receive a reply within two working days, please use this escalation form to escalate.
Hello @MSF-SP-Yasar, I tested this on my end using the same setup and was able to successfully load the local workbench and add the SPFx web part without issues.
SPFx Version: 1.18.2 Node.js Version: 18.20.4 Commands Used: gulp serve and npm run serve Browser Tested: Microsoft Edge (latest)
It might help to try the following steps on your end:
- Ensure you're running the correct Node.js version (≥18.17.1 as required by SPFx 1.18.2)
- Clear the browser cache or try incognito mode
I ran into a similar issue, and manually trusting http://localhost:4321 resolved it for me.
@MSF-SP-Yasar, Just following up on issue. Were you able to resolve the issue on your end?
Hi,
I upgraded my SPFx to 1.12.1 and Node versions to v22.20 but still has the same issue. @gretchunkim thanks for your advice but it did not work for me.
@MSF-SP-Yasar, Thanks for the update and for trying the suggestions. Since you're still encountering the issue, could you please try the following steps:
- After running gulp serve, open the local workbench.
- Once it's loaded, try clicking on the “Preview” button (top-right corner) and then “Edit” again.
- Sometimes this triggers the proper loading of the web part toolbox and resolves the issue temporarily.
- Also, try doing a hard refresh (Ctrl + F5) to clear any cached scripts that might be interfering.
Let us know if this helps, or if the issue persists.