It seems you hit a WebGL error while trying to edit a mockup template. We understand that it's frustrating when things don't work like they are supposed to, so here are a few suggestions on how to fix this issue ASAP:
- Update your web browser - make sure you are using the latest version.
- Try a different browser - we reccommend Google Chrome for best performance.
- Already a Chrome lover? - Turn on Hardware Acceleration under Chrome Settings - Advanced
If the Hardware Acceleration option did not fix the issue, then go to chrome://flags and enable Override software rendering list
In case none of the above methods work for you, then you can still use our static product editor to customize templates (Look for the Show Static Editor button below the right sidebar).