Fixing the block preview error in Gutenberg

If the editor shows “This block has encountered an error and cannot be previewed”, the fix lives in our current troubleshooting flow. This page points you to the right guide depending on what you are running.

Where to go next

Start with the general guide, then check the LT-specific one if you are on a newer block-based theme.

• Block and editor issues: see Block errors and editor troubleshooting for preview failures, invalid content warnings, plugin conflicts, and post-update regressions.
• LT themes: if you are on one of our newer block-based themes, also review LT theme compatibility and post-update troubleshooting.
• Gutenberg plugin: if the Gutenberg plugin is active, deactivate it first and retest before digging deeper.