Linter ESLint tooltip customization

I’d like to know how to customize (font, color, embedded elements, …)
the tooltips popup panels that are shown when I hover on error or alert
inside the document and in the gutter.
CodeMirror 6.
Thank You.

After some attempts I found a solution for changing the background color
of tooltip linter:

    const tooltipTheme = EditorView.theme({
        ".cm-tooltip-lint": { backgroundColor: "yellow" }

    new EditorView({
        state: EditorState.create({
            doc: "console.log();",
            extensions: [
                linter(esLint(new Linter())),
        parent: document.body

But for example how can I change the content of the linter tooltip ?
Thanks if someone can give me help.

The content, as in the error messages, or the style? The error messages can only be changed by wrapping the lint source in another function that transforms them. Styling the content goes in precisely the same way you already showed — create a theme that adds CSS rules.

I need for example 2 things:

  1. Change the error message text of the linter tooltip
  2. Add a button to the linter tooltip for suggesting available actions to the user
    to solve the problem shown in the error message.
    How can I do ?
    Can someone give me EXAMPLE CODE of this ?
    Thank You in advance.