Problems with MJML-Generated Responsive Emails' Compatibility with Gmail

Exploring Responsive Email Challenges in Gmail

Using MJML to create responsive emails enables a simplified design process and ensures compatibility with a wide range of email clients. But problems can occur when these emails are viewed in email clients like Gmail, which could not provide the responsiveness that MJML templates aim to provide. This disparity frequently shows up when developers test their emails using services like Litmus, which demonstrate how well the design works across several clients, only to discover that the responsive parts of the design don't work as effectively when sent through Gmail.

Usually, the way HTML is imported into the Gmail interface is the source of this problem. Common procedures like copying and pasting HTML that has been produced from a browser straight into an email might cause serious display problems. These issues draw attention to the necessity for a more practical way to guarantee that responsive designs retain their functionality on all viewing platforms, especially in the case of popular email services like Gmail.

Applying Techniques for Responsive Email Compatibility

Gaining more control over the functionality of the supplied scripts is essential to enhancing the Gmail responsiveness of emails generated with MJML. The first script focuses on a client-side method of converting linked or embedded stylesheet CSS styles inside an HTML document into inline styles using JavaScript. This is important since MJML usually relies on styles defined in headers or external stylesheets, which Gmail does not fully support. All CSS rules are applied directly to the HTML elements as inline styles thanks to the script's programmatic inlining of these styles utilizing the convertStylesInline method. Using the appropriate elements' selectors as a guide, this approach applies each CSS rule to each one as iteratively derived from the style elements. This procedure makes sure that the styling continues even in Gmail's constrictive email environment, where inline styling is preferred for consistent display.

The second script aims to handle the translation of MJML to HTML on a server-side using Node.js. This method is very helpful for automating and optimizing the email generating process in development environments. Developers can submit POST requests containing MJML markup and obtain responsive HTML in reply by configuring an Express server and using the MJML library. This backend configuration is perfect for applications that need to generate a large number of emails since it not only makes the conversion easier, but it also offers a mechanism to handle multiple conversions dynamically and effectively. When Express.js is used, the script's capacity to handle online requests and responses is improved. This provides email marketers and developers with a strong option to preserve the integrity of their email designs on several platforms, including Gmail.

<script>
// Function to convert style attributes to inline styles
function convertStylesInline(htmlContent) {
    const container = document.createElement('div');
    container.innerHTML = htmlContent;
    const styleSheets = Array.from(container.querySelectorAll('style'));
    styleSheets.forEach(style => {
        const rules = style.sheet.cssRules;
        Array.from(rules).forEach(rule => {
            const { selectorText, style: cssText } = rule;
            container.querySelectorAll(selectorText).forEach(elem => {
                elem.style.cssText += cssText.cssText;
            });
        });
        style.remove();
    });
    return container.innerHTML;
}
</script>
<script>
// Example usage
const mjmlHtml = document.getElementById('your-mjml-html').innerHTML;
const inlineHtml = convertStylesInline(mjmlHtml);
document.getElementById('your-mjml-html').innerHTML = inlineHtml;
</script>

const express = require('express');
const mjml2html = require('mjml');
const app = express();
app.use(express.json());
app.post('/convert-mjml', (req, res) => {
    const { mjmlContent } = req.body;
    const htmlOutput = mjml2html(mjmlContent);
    res.send({ html: htmlOutput.html });
});
app.listen(3000, () => console.log('Server is running on port 3000'));

Methods for Adding HTML That Is Responsive to Gmail

The usage of media queries and their limits within Gmail's client is an important but little-discussed component of making sure emails seen in Gmail are responsive. The key to responsive design is media queries, which allow the email content to adjust to the screen size of the device being viewed. Nevertheless, when Gmail processes incoming emails, it removes some CSS, including some styles seen in media queries. The desired responding behavior may be lost as a result of this. In order to get around this, designers must use CSS inlining tools more often to make sure that important responsive styles are applied to the HTML components directly. Additionally, media queries are not the only method available for applying styles under specified conditions. Gmail normally supports techniques like CSS attribute selectors.

Moreover, it is essential to comprehend the quirks of Gmail's rendering engine. Gmail employs its own proprietary engine, which can read CSS differently from web browsers, to render emails instead of using the standard web browser engine. When viewed in web browser-based email applications like Litmus, emails that appear flawless can have unanticipated consequences due to this disparity. Thus, in addition to using universal testing platforms, developers should think about testing their email designs especially in Gmail to make sure that their emails display well not only across a range of devices but also in Gmail's particular environment.