Electron makes things worse: it is not secure. Electron has many security vulnerabilities. The latest version is still based on old Chromium (58 & 59) so it inherits many of the security vulnerabilities published in Chromium 60, 61 and 62
This doesn't make it safe -- consider a lower level library inside Chromium can be exploited when processing input data. Your chat app can be exploited by receiving a crafted image. This actually happened in image processing library and network library in Chromium.
It's not as simple as you thought. Consider a bug in the image decoding library Chromium used that can be exploited by simply sending a crafted image in the chat.
Using Electron is a bad idea: it's not secure. Electron has many security vulnerabilities. The latest version is still based on old Chromium (58 & 59) so it inherits many of the security vulnerabilities published in Chromium 60, 61 and 62