To remove render-blocking CSS resources in AEM, you can use techniques such as:
- Minifying and concatenating CSS files to reduce the number of resources being loaded
- Using inline CSS for critical above-the-fold content and deferring non-critical CSS
- Utilizing server-side rendering to prioritize loading of necessary CSS
- Leveraging techniques like lazy loading and asynchronous loading of CSS files
- Utilizing browser caching to reduce the need for repeated loading of CSS resources.
By implementing these strategies, you can help reduce render-blocking CSS resources in AEM and improve the overall performance and speed of your website.
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What are the common mistakes to avoid when removing render blocking CSS in AEM?
- Not properly analyzing which CSS files are essential for rendering above-the-fold content. It is important to identify critical CSS and inline it while removing non-essential or unused CSS.
- Removing CSS without considering its impact on the overall appearance and functionality of the website. It is important to thoroughly test the website after removing render-blocking CSS to ensure that it still looks and functions as intended.
- Over-relying on automated tools to remove render-blocking CSS. While tools can be helpful in identifying and removing unnecessary CSS, they are not always foolproof and may remove essential stylesheets.
- Not considering the impact of deferred loading or asynchronous loading of CSS on the user experience. Care should be taken to ensure that the website still loads quickly and smoothly after removing render-blocking CSS.
- Failing to regularly review and update the list of render-blocking CSS files. As the website evolves and new features are added, the list of critical CSS may change, so it is important to regularly review and update the list of render-blocking CSS files.
What is render blocking CSS and why is it important to remove it in AEM?
Render blocking CSS refers to CSS files that prevent the browser from rendering the webpage until they have been fully loaded. This delay in rendering can disrupt the user experience and slow down the loading time of the webpage.
In AEM, it is important to remove render blocking CSS to improve page loading speed and overall performance. By eliminating or reducing the amount of render blocking CSS, you can optimize the rendering process and ensure that the webpage loads quickly and smoothly for users. This can lead to improved user satisfaction, increased engagement, and potentially higher search engine rankings.
How to use async and defer attributes for loading CSS in AEM?
To load CSS asynchronously or defer its loading in AEM, you can add the async or defer attributes to the tag in your HTML template or component.
Async attribute:
- Open the HTML template or component where you have included the CSS file.
- Locate the tag that references the CSS file.
- Add the async attribute to the tag like this:
- Save the changes and upload the modified file to AEM.
Defer attribute:
- Open the HTML template or component where you have included the CSS file.
- Locate the tag that references the CSS file.
- Add the defer attribute to the tag like this:
- Save the changes and upload the modified file to AEM.
By adding the async or defer attribute to the tag, the browser will load the CSS file asynchronously or defer its loading, respectively. This can help improve the performance of your website by allowing other content to load first before the CSS file is fetched and applied.
What are the potential security risks associated with removing render blocking CSS in AEM?
- Content Flickering: Removing render blocking CSS may cause content to flicker when users access a page, leading to a poor user experience.
- Unstyled Content: Without render blocking CSS, the content may appear unstyled or disorganized on the page, making it difficult for users to read or navigate.
- Performance Issues: Removing render blocking CSS may negatively impact the performance of the website, leading to slower page load times and potentially affecting search engine rankings.
- Layout Shifts: Removing render blocking CSS can cause layout shifts or unexpected changes in the appearance of the page, which can be confusing for users and disrupt their browsing experience.
- Security Vulnerabilities: In some cases, removing render blocking CSS can expose potential security vulnerabilities, such as allowing malicious scripts to be executed on the page or exposing sensitive information to unauthorized users.
- Accessibility Issues: Without render blocking CSS, the website may not be accessible to users with disabilities who rely on specific styles to navigate and interact with the content.
