13 Common WordPress Block Editor Problems and How to Fix Them

The WordPress block editor, also known as Gutenberg, is a powerful content creation tool. However, like any software, it‘s not without its flaws. In this comprehensive guide, we‘ll share the 13 most common block editor issues users face and proven solutions to resolve them.


1. The Editor Has Encountered an Unexpected Error

This is by far the most common error people see in the block editor. You‘ll know it‘s happened when you see a message saying:

"The editor has encountered an unexpected error. Please try reloading this page."

There are a few potential causes for this vague, but annoying issue:

Plugin Conflicts

Like most WordPress problems, incompatible or buggy plugins are often the culprit. To troubleshoot, switch your site to a default theme and deactivate all plugins. Then reactivate them one by one until you isolate the problematic plugin.

Once identified, check if the plugin has an update available. If so, update it and test if that resolves the error. Alternatively, you can temporarily deactivate the plugin to confirm it‘s causing the problem.

If the error persists even with all plugins disabled, move on to the next troubleshooting tips below.

Server Resource Constraints

Heavy site traffic or inadequate server resources can also cause this error. When the server is under load, it may fail to provide a valid response to the editor.

Check with your host to rule out any server-side issues. Switching to a managed WordPress host with guaranteed resources often solves this problem.

Permalink Structure Misconfiguration

An invalid permalink structure is another potential culprit for the unexpected error. Go to Settings > Permalinks and switch to the default setting temporarily. See if that stops the error from appearing.

If so, reconfigure your permalinks to the desired structure again. Make sure to select one without any special characters or unnecessary elements.

Corrupted Browser Cache

An accumulation of corrupt files in your browser cache can also interfere with the editor‘s functionality. Clear your browser‘s cache and cookies to eliminate this possibility.

Outdated WordPress Version

Using an outdated version of WordPress can also cause functionality issues with the block editor. Ensure you‘re running the latest version of WordPress to benefit from bug fixes and improvements.

Also, make sure your site meets the minimum required PHP version. You can check this under Tools > Site Health.

2. The Block Editor Keeps Crashing

Another common complaint is the editor freezing and crashing unexpectedly while editing a post or page.

When this happens, you‘ll see the following error message:

"The editor has encountered an unexpected error. Please try reloading this page. Copy Post Text. Copy Error."

Here are some tips to stop the editor from crashing:

Update Outdated Plugins

Like the previous issue, incompatible plugins can cause the editor to crash frequently. Check your plugins and ensure you‘re running the latest versions.

Plugins with known bugs or conflicts with the block editor are particularly problematic. Check the plugin developer‘s changelog to see if the crashes have been addressed in newer versions.

Switch to a Default Theme

Your custom theme‘s code may also be responsible for the editor crashes. Switch to a default WordPress theme like Twenty Twenty-Two to isolate whether the theme is the culprit.

If the crashes stop occurring, then your theme needs investigation. Try updating to the latest theme version or reporting the issue to the theme developer.

Disable Plugin and Theme Editors

The WordPress plugin and theme editors allow you to modify code directly from the admin dashboard. If a plugin or theme is corrupted via the editor, it can cause block editor crashes.

Temporarily disable the plugin and theme editor via wp-config.php to rule out this possibility:

define( ‘DISALLOW_FILE_EDIT‘, true );

Update WordPress

An outdated WordPress version can also be responsible for a crashing block editor. Ensure you‘re running the latest WordPress update.

Also check if your server meets WordPress‘ minimum PHP requirements. You can view this under Tools > Site Health.

3. Encountering Invalid JSON Response Error

When trying to save or update a post in the block editor, you may encounter the following error message:

"The response is not a valid JSON response."

This frustrating error indicates that WordPress encountered an issue trying to communicate with your website‘s server.

Here are a few potential fixes:

Verify REST API is Working

The block editor uses the WordPress REST API to send and receive information from the database. If the REST API is misconfigured or blocked, it will cause the invalid JSON error.

Go to Tools > Site Health and check the REST API section for any issues. The "Loopback request" test is particularly important.

If the REST API has problems, try troubleshooting the cause or contact your host‘s support.

Confirm WordPress Address and Site Address

Under Settings > General, check that the WordPress Address and Site Address match and are correct. If the site URL is incorrect, it can cause invalid JSON errors.

Switch to Default Theme

As the error appears during saving, your custom theme‘s code may be interfering. Switch to a default theme like Twenty Twenty-Two as a troubleshooting step.

Update Permalink Settings

Invalid JSON responses can also occur with a misconfigured permalink structure. Double-check your permalink settings under Settings > Permalinks.

Try resetting to the default structure as a test. Avoid unnecessary elements like %postname% or special characters.

Review Server Error Logs

Check your server error logs to see if any clues point to the source of the invalid JSON error. Your host should be able to provide instructions for accessing logs.

Reviewing logs can reveal problems like exhausted memory, script errors, or overridden security rules.

4. Encountering "Updating Failed" Error

When trying to publish or update a post in the block editor, you may see the following error message:

"Updating failed. You are probably offline."

This indicates that the editor is unable to communicate with your WordPress database for some reason. Here are some troubleshooting tips:

Check Your Internet Connection

First, ensure that you have an active internet connection. If you lost connectivity, this can instantly cause the updating failed error message.

Increase PHP Memory Limit

If your server has inadequate PHP memory allocated to WordPress, it can cause this issue. Increase the memory limit to at least 64MB, or 128MB for larger sites.

You can do this by adding the following line to your wp-config.php file:

define( ‘WP_MEMORY_LIMIT‘, ‘64M‘ );

Disable Plugins

As usual, buggy plugins can also interfere with the editor‘s ability to update content. Disable your plugins and retest updating posts.

If the issue disappears, reactivate plugins one-by-one until you isolate the problematic plugin.

Use Default Theme

Switch to a default WordPress theme like Twenty Twenty-Two to determine if your custom theme is causing the problem.

Review Server Error Logs

Check your server error logs to see if any issues are preventing WordPress from updating content as expected. There may be clues such as PHP out of memory errors.

Contact Host Support

If you‘re unable to resolve the issue through other troubleshooting, contact your WordPress host‘s support team. Technical problems like server misconfigurations can cause this error.

5. Adding or Removing Blank Space Between Blocks

Excess whitespace between blocks is another common complaint about the editor. Here are some tips to customize spacing:

Use the Spacer Block

The simplest way to add more space between blocks is using a Spacer block. Just insert it between any blocks needing more separation.

You can set the height of the spacer block by dragging it larger or smaller.

Adjust Block Settings

Some blocks like images and cover blocks have spacing adjustment settings built-in. Look for a "Space" or "Spacing" option to customize.

Utilize CSS

For more advanced control, you can use custom CSS code to modify block spacing site-wide or for individual pages.

For example, to reduce default spacing, you can use:

.wp-block {
  margin-top: 0;
  margin-bottom: 0;

Or target individual blocks like:

.wp-block-cover {
  padding-top: 20px;
  padding-bottom: 20px; 

Use Plugins

Plugins like CSS Hero make it easy to customize block spacing without editing code. They add spacing controls through a visual interface.

6. Pasting Text Loses Formatting

Frustratingly, copy and pasting text into the block editor often strips formatting like bold and italics.

Here are some tips to maintain formatting when pasting:

Use Keyboard Shortcuts

After pasting text, highlight it and use keyboard shortcuts to reapply formatting. For example, CTRL + B to bold text.

Make this a habit each time you paste text to reinstate formatting.

Paste as Plain Text

When copying text, paste it as plain text rather than formatted text. You can then use block editor tools to apply formatting.

Use formatting tools

Highlight the pasted text and use the formatting tools in the block editor toolbar to style it appropriately.

Switch to Code Editor

Paste the text in the code editor view instead. This preserves formatting so you can switch back to visual editing.

Use Selective Paste

When pasting, use CTRL+SHIFT+V instead of CTRL+V. This opens a window that lets you choose how to handle formatting.

Install Paste as Text Plugin

A plugin like Paste as Text automatically strips formatting when pasting into the block editor. It saves you having to do it manually.

7. Images Fail to Upload to Media Library

If images disappear or fail to upload into the media library, there are a few likely culprits:

Confirm File Types

Double-check that the images you‘re uploading are supported file types like JPG, PNG, and GIF. Unsupported formats will fail to upload.

Increase File Upload Size Limit

If the images exceed the maximum upload size limit set by your server, they will get rejected. Increase the limit to accommodate your files.

Review Server Error Logs

The server error logs may reveal hints about why uploads are failing, like exceeding disk space or memory limits. Ask your host for help accessing logs.

Validate File Permissions

Incorrect file permissions for the /wp-content/uploads/ folder will cause upload failures. Validate write permissions are set correctly.

Switch to Default Theme

As usual, buggy theme code can also sometimes interfere with uploads. Switching to a default theme isolates if your custom theme is the issue.

Disable Plugins

If uploads succeed with all plugins disabled, reactivate them individually to identify any incompatible plugins.

8. Receiving "HTTP Error" When Uploading

Another common upload error is seeing generic "HTTP Error" messages without detail when uploading files in the media library.

This occurs when the WordPress server encounters a temporary error during the file upload process. Some potential fixes include:

Allow Temporary Error Recovery

Don‘t immediately retry the upload. Allow a few minutes for the server to recover on its own from the temporary error.

Increase PHP Memory Limit

If the server is running low on memory, it may fail on image uploads. Increase the PHP memory allocated to WordPress.

Adjust .htaccess File

Upload errors can stem from incompatible or broken .htaccess rules. Try resetting the .htaccess file.

Validate Server Hardware Resources

If your WordPress host is underpowered, image uploads may fail during times of high traffic or load. Contact them to confirm sufficient resources.

Change Image Editing Library

Switching the image editing library used in WordPress can potentially resolve inconsistencies causing this issue.

Refresh Authentication

Sometimes just logging out and back in can reset authentication issues preventing uploads.

9. Scheduled Posts Do Not Publish

WordPress lets you schedule posts to publish in the future. But sometimes, they fail to go live at the scheduled date and time.

Double-Check Scheduled Date

It may sound obvious, but always review the scheduled publish date is correct before troubleshooting further.

Verify Timezone Settings

Under Settings > General, check your site‘s timezone is set properly. If it doesn‘t match your local time, your posts may miss their schedule.

Increase WP Memory Limit

Like other issues, a limited PHP memory allocation can cause scheduled publishing to fail. Increase the WP memory limit to a minimum of 64MB.

Resolve Plugin Conflicts

Incompatible plugins are a prime cause for missed scheduled posts. Disable plugins and check if scheduled publishing works properly.

Clear Server Cache

A full server cache flush can clear up stale cached data or corruption that may block scheduled publishing.

Validate wp-cron Functionality

WordPress scheduled posts rely on wp-cron, which can sometimes be disrupted. Check wp-cron is working correctly under Site Health.

10. Alignment Adjustments Revert or Do Not Apply

When adjusting text or image block alignment in the editor, the changes may not stick.

No matter how many times you center align a block, it reverts to left aligned. What gives?

Disable Gutenberg Plugin

If you have the Gutenberg plugin installed alongside the block editor, this can cause alignment issues. Simply deactivate it.

Customize Block Template

For reusable blocks, the underlying block template may override alignment settings. Modify it in Tools > Template Editor.

Fix Theme Styles

Excessive or invalid CSS rules in your theme‘s style.css file can interfere with block alignment. Try switching to a default theme.

Utilize !important

For persistent alignment issues, add the !important CSS declaration to your custom alignment rules. This forces them to override other CSS styles.

Install Alignment Control Plugins

Plugins like WP Block Align and Block Options add enhanced alignment settings and control to the editor.

11. Embeds Show Incorrect Thumbnails on Facebook

When sharing posts with embedded content on Facebook, it sometimes picks the wrong thumbnail image.

To control what image it uses:

Specify Open Graph Image in Editor

Use the "Social" tab in the document settings sidebar of the editor to specify an Open Graph image. This overrides Facebook‘s auto-selected image.

Install Yoast SEO Plugin

The Yoast SEO plugin lets you set a customized Open Graph image for each post. This image will display on Facebook.

Include og:image Meta Tag

If using a SEO plugin, insert a custom og:image meta tag directly into your post template file. Place it above the Yoast or other SEO plugin metadata output.

Adjust Image Placement

Position the image you want as the thumbnail at the start of the post content. Facebook will select the first image on the page to use for thumbnails.

Feature Image > Content Images

Facebook also prioritizes images set as the Featured Image for a post over inline images in the content. So set your desired image as the Featured Image.

12. Facebook and Instagram Embeds Do Not Work

Recent changes by Facebook broke the previous embedding of Facebook and Instagram posts in WordPress. Now when you try to embed them, you‘ll just see a plain URL.

To embed Facebook and Instagram content again, you need to install a plugin that provides updated integration, such as:

  • Smash Balloon Facebook & Instagram Feeds Plugin
  • Social Post Feed Plugin
  • Facebook for WordPress by Facebook

These plugins utilize current Facebook API access to pull in profiles, pages, groups, images, albums, reviews, events and more into your WordPress site.

The Social Post Feed Plugin lets you embed posts from Facebook, Instagram, Twitter, Youtube, and more with customizable layouts.

13. Unable to Preview Embeds in Editor

Some users have reported being unable to preview embedded content like YouTube videos in the block editor. Instead of a live preview, a generic "Preview unavailable" message shows.

This frustrating issue appeared after WordPress 5.5 introduced lazy loading for embedded content.

To get previews working again:

Update WordPress

Recent WordPress versions have resolved this preview issue. Ensure your site is running the latest WordPress update.

Disable Lazy Loading

Install a plugin like Disable Embeds Lazy Load which will deactivate lazy loading and restore embed previews.

Preview on Frontend

You can preview properly in the frontend rather than relying on the post editor preview. Just view your published draft.

Switch to Classic Editor

If all else fails, swap back to the classic editor. Previews work fine there, though you‘ll lose access to blocks.

We hope this guide covers the most common block editor issues users face and provides actionable solutions to overcome them. Let us know if you have any other persistent problems with the editor that we should include!

Written by Jason Striegel

C/C++, Java, Python, Linux developer for 18 years, A-Tech enthusiast love to share some useful tech hacks.