Cross platform application, is it a myth?

Question

Cross-platform

Today I had some dispute about the cross-platform nature of our application, we have a web application and it has a desktop shell, and my colleague very persistently tells me that this electron creates one application that can be installed on both Windows and Mac Os .
I understood the word "cross-platform" on the electronom website as that our application itself written in: node.js, react, html, css will be K-P, and the interpreter (shell created by electronom) will be different for each OS (well, there will be several ), such as browsers for different operating systems that will open the same site
Maybe I’m somehow behind the times, but in my opinion one application installer for different OSes is a game (well, in principle, you can detect which OS and, depending on this, give the necessary packages and directories for installation, but I haven’t seen this yet)
Please clarify situation)

Answer 1

No, electron creates three separate, albeit functionally identical applications for each platform. There are no cross-platform executables, as far as I know (well, if only FatELF is a container with elfs for several platforms). Inside, the same html / js / css is everywhere, but it is wrapped in different binaries depending on the platform.

Answer 2

Electron is an open source library developed by GitHub for building cross-platform desktop applications with HTML, CSS, and JavaScript. Electron accomplishes this by combining Chromium and Node.js into a single runtime and apps can be packaged for Mac, Windows, and Linux.
That is, nodejs + Chromium browser comes to you and on top of this - your application in one executable file.
Technically, they're not lying, but...

Answer 3

The installer, in the usual meaning of "installer" is an executable file, so it is different for each platform.
And an electron is a v8 type that runs your node.js code and renders the frontend. And this v8, in which everything turns around, is also compiled separately for each platform, on which it will then be launched.
A cross-platform application is one source code that compiles for different OSes, not one binary that runs on different OSes. This is basically impossible.