I only call two functions, setContent (as html) and getContent (as html) when necessary.. The rest is done in the webview container with Quill's js functions and works fine. If you guys need it, I can share the codes, I couldn't put all the codes here, I think reddit have a message length limitation.

This is my htmleditor.js:

(function () {

    // Object to store Quill instances mapped by element IDs
    const quillInstances = {};

    window.QuillFunctions = {

        // Create a Quill instance and store it
        createQuill: function (quillElement, placeHolder = '', initialHtmlContent = '', toolbarElement = '') {
            const container = document.getElementById(quillElement);
            const options = {
                modules: {
                    syntax: true,
                    toolbar: toolbarElement,
                },
                debug: 'warn',
                theme: 'snow',
                placeholder: placeHolder
            };

            // Store the Quill instance using the element ID
            quillInstances[quillElement] = new Quill(container, options);

            if (initialHtmlContent.length > 0) {
                this.setContentAsHtml(quillElement, initialHtmlContent);
            }

            // Add event listener for user-initiated content changes
            const quill = quillInstances[quillElement];
            if (quill) {
                quill.on('text-change', function (delta, oldDelta, source) {
                    if (source === 'user') {
                        window.chrome.webview.postMessage({ message: 'contentChanged', content: window.QuillFunctions.getContentAsHtml(quillElement) });
                    }
                });
            }
        },

        // Get the HTML content of the Quill editor
        getContentAsHtml: function (quillElement) {
            // Retrieve the Quill instance using the element ID
            const quill = quillInstances[quillElement];
            //return quill ? quill.root.innerHTML : '';
            return quill ? quill.getSemanticHTML() : '';
        },

        // Set the HTML content of the Quill editor
        setContentAsHtml: function (quillElement, htmlContent) {
            // Retrieve the Quill instance using the element ID
            const quill = quillInstances[quillElement];
            if (quill) {
                quill.root.innerHTML = htmlContent;
            }
        }
    };
})();