Notifications Broken when adding an extesion

[davidfornas]

I am suffering a weird issue I don't know how to solve or debug. I created a Hello World extension and tried in both electron and browser. I can use the command and see the notifications.

However, as soon as I create a new extensión (I used yo theia-extension standalone) I start not being able to see the message pop-up. I can see the notifications Bell wirh a number 1 but nothing else happens.

This happenes while copying some code to modify AboutDialog that uses react from Theia IDE. Could this be related? Even if I delete the new extensión the problem persists.

What can I do to debug the issue?

[msujew]

Hey @davidfornas,

Do you get any errors in the browser dev console when the application starts or when the notification triggers/should appear?

[davidfornas]

I think it has happened when I have added "peerDependencies": { "react": "^16.8.0" } to my second extension.

I think I started seeing this error:

2025-08-20T18:56:19.532Z root ERROR The above error occurred in the <ScrollBar> component:

ScrollBar@http://localhost:3000/vendors-node_modules_theia_messages_lib_browser_messages-frontend-module_js.js:1134:20
div
NotificationCenterComponent@http://localhost:3000/vendors-node_modules_theia_messages_lib_browser_messages-frontend-module_js.js:110:9
div

Consider adding an error boundary to your tree to customize error handling behavior.
Visit https://reactjs.org/link/error-boundaries to learn more about error boundaries.

and also this error repeatedly:

2025-08-20T18:56:19.615Z root ERROR The above error occurred in the <ForwardRef(TextareaAutosize)> component:

TextareaAutosize@http://localhost:3000/vendors-node_modules_theia_scm_lib_browser_merge-editor_merge-editor_js-node_modules_theia_sc-59ad23.js:11261:27
SearchInWorkspaceTextArea@http://localhost:3000/vendors-node_modules_theia_search-in-workspace_lib_browser_search-in-workspace-factory_js.js:169:9
div
div
div
div
div

Consider adding an error boundary to your tree to customize error handling behavior.

I added it copying from Theia IDE "theia-ide-product-ext".

[msujew]

I see, that might explain it? Theia itself is using react@18.2.0:

theia/packages/core/package.json

Lines 60 to 61 in 1539178

	"react": "^18.2.0",
	"react-dom": "^18.2.0",

You can import react directly from Theia by importing from '@theia/core/shared/react'. If that doesn't work, please provide a reproducible example.

[davidfornas]

Correct, thanks! This react dependency was messing with the rest of the application I guess. I switched my code to use directly and it worked '@theia/core/shared/react'.