How to access the visual editor from JavaScript in MediaWiki?

In MediaWiki 1.36.1 with Skin:Timeless, the following JavaScript code doesn't work. I get in browser console:

Your skin is incompatible with VisualEditor.
See https://www.mediawiki.org/wiki/Extension:VisualEditor/Skin_requirements for the requirements.

That's strange because right after installing Visual Editor, when I first came to edit, I was asked if I want to use the source code editor OR the visual editor and when I chose the Visual Editor, it worked fine.

let domain = window.location.host;
let protocol = window.location.protocol;
let h1 = document.querySelector("h1");

window.addEventListener('keydown', function(event) {
    if (event.altKey && event.shiftKey && event.key === 'E') {
        window.location.href = `${protocol}//${domain}/index.php?title=${h1.innerText}&veaction=edit`;
    }
});

Why do I get the above error in console and how to solve it?

Notes

• I emphasize the veaction=edit instead just action=edit in this code
• Credit for user:hkotsubo‭ who wrote most of that code