# Mozilla vtkjs rendering stopped working
**URL:** https://discourse.vtk.org/t/mozilla-vtkjs-rendering-stopped-working/6688
**Category:** Web
**Created:** [September 24, 2021, 9:59am UTC](https://discourse.vtk.org/t/mozilla-vtkjs-rendering-stopped-working/6688 "2021-09-24T09:59:09Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@SArbabi](https://discourse.vtk.org/u/SArbabi)
#### Post date: [September 24, 2021, 9:59am UTC](https://discourse.vtk.org/t/mozilla-vtkjs-rendering-stopped-working/6688/1 "2021-09-24T09:59:10Z")
On a web app that I created before with vtk.js and was working quite reliably, just recently I’m getting this issue in firefox which makes it not load the object in the scene and keeps the scene black:
```auto
Use of drawWindow method from CanvasRenderingContext2D is deprecated. Use tabs.captureTab extensions API instead https://developer.mozilla.org/docs/Mozilla/Add-ons/WebExtensions/API/tabs/captureTab
```
the app is still working the same way in Chrome, yet.
Any thoughts much appreciated.
Best
---
### Author:  [@Sebastien\_Jourdain](https://discourse.vtk.org/u/Sebastien_Jourdain)
#### Post date: [September 24, 2021, 2:43pm UTC](https://discourse.vtk.org/t/mozilla-vtkjs-rendering-stopped-working/6688/2 "2021-09-24T14:43:26Z")
You will need to be more specific.
Which version of vtk.js? Which backend (WebGL/WebGPU/Auto)?
---
### Author:  [@Forrest](https://discourse.vtk.org/u/Forrest)
#### Post date: [September 24, 2021, 3:18pm UTC](https://discourse.vtk.org/t/mozilla-vtkjs-rendering-stopped-working/6688/3 "2021-09-24T15:18:46Z")
That error doesn’t seem to be related to vtk.js. It looks like an extension error. In any case, we don’t use drawWindow in vtk.js.