pencil tool to draw, on a new image on jspaint.app the white background disappears and becomes black dots

[tgkprog]

using pencil tool to draw something, on a new image on jspaint.app the white background disappears and becomes black dots/ like invisible, see video: https://youtu.be/ssVwDWdsWhc

on Chrome latest version :
Version 120.0.6099.216 (Official Build) (64-bit)

OS Ubuntu 22.04.3 LTS

Hardware Acer Aspire E5-573G

Gimp works fine. other websites like google docs work fine

[1j01]

This sounds a lot like 1j01/jspaint#328 except on Ubuntu instead of macOS.
I'm unable to reproduce the behavior on Chrome version 121.0.6167.85 (Official Build) (64-bit) on Ubuntu 22.04.3 LTS
This is not likely a bug in jspaint. You could try upgrading or downgrading Chrome, but if the latest version doesn't work, this may need to be reported to the Chrome developers.