When publishing posts on a WordPress blog, you might encounter issues where thumbnail images do not appear on recent posts or category pages. Additionally, there may be instances where thumbnails get distorted when sharing WordPress posts on Facebook. Let's discuss some troubleshooting steps for resolving issues with WordPress thumbnail images (featured images) not displaying correctly.
Solutions for WordPress Thumbnail Image Display Issues
If No Featured Image is Specified
The following shows a case where a specific post does not display a thumbnail when using the Newspaper theme for a WordPress site.
When you publish a post, if the thumbnail is absent or only the default thumbnail (which appears when no featured image is set) shows up, it indicates a potential issue.
To resolve this, first check if a featured image is set for the post. If there is a Set Featured Image button visible on the editing screen, it means no featured image has been designated. Clicking on this button allows you to set a representative image, thus solving the problem.
Setting a featured image is fundamental to using WordPress effectively.Purchasing a book on basic functionality of WordPress can be helpful.
Check Thumbnail Display Settings
This blog is configured to show thumbnails on its latest posts, categories, and archive pages.
If all post items are missing thumbnail images on the latest posts or category pages, it may be due to settings in the blog configuration prohibiting thumbnail displays.
For instance, in the GeneratePress theme, if the Display featured images option in the Appearance » Customize » Layout » Blog » Featured Images » Archives tab is turned off, the featured images will not appear on the blog pages (such as latest posts and category pages).
After checking this option and saving changes, clearing the cache will enable the featured images (thumbnails) to show up properly on the blog page.
If Migrating from Wix or Using Automated Posting Plugins
When migrating from platforms like Wix to WordPress, the method of migration might leave the featured images unset. This would result in the absence of thumbnails on archive pages, including latest posts, categories, and tags.
Moreover, if you post about affiliate products, such as those from Amazon, using automated tools or plugins, featured images might not be set.
As a reference, it is possible to modify the posts migrated from platforms like Wix with ChatGPT after transferring via plugins.
In such cases, utilizing the Featured Image from URL (FIFU) plugin allows you to forcefully set the first image as the featured image if none has been assigned.
Navigate to WordPress Admin » FIFU » Automatic tab and check the setting Automatically set featured media from post content in the Automatic Settings. Turn the option for "Automatically set featured media from post content" to ON to enforce the first image as the featured image.
The FIFU plugin is particularly useful when images are inserted via external URLs.
In previous versions of FIFU, there was an option to specify which image to set as the featured image, but the current free version defaults to setting the first image as the featured image.
Plugin Conflicts
Sometimes, plugin conflicts may cause featured images not to display. This is especially common with caching plugins or speed optimization tools like Autoptimize, Clearfy.
If you have set a featured image and it still doesn't show, try deactivating all plugins to see if that resolves the issue. If the thumbnail appears after all plugins are deactivated, you can reactivate them one by one to identify the conflicting plugin.
When Using Jetpack Plugin's Image CDN
Occasionally, using the image CDN feature of the Jetpack plugin can lead to thumbnail-related issues.
Check if the image CDN module of Jetpack is enabled. If it is, try deactivating it to see if that resolves the problem.
Note that Jetpack is bundled with hosted WordPress (WordPress.com), which is optimized for speed. However, on self-hosted WordPress sites, it can slow down site performance, so it's advisable to minimize its use. If using Jetpack for statistics, consider activating only the statistics module while deactivating all other modules.
Issues with Thumbnail Display When Sharing WordPress Posts on Facebook
Facebook sometimes reports issues where thumbnails break when sharing WordPress posts.
The problem arises when Facebook changes how it handles image file names that contain non-English characters, such as Korean letters. If the shared image file name includes such characters, the image may not display correctly.
To resolve this issue, rename the image file to ensure it does not contain non-English characters, and the problem should be rectified. For detailed information on thumbnail issues when sharing on Facebook, refer to the following articles.
Additionally, using image CDN features like Jetpack’s can also lead to missing images during Facebook sharing.