How to get past the “This block has encountered an error and cannot be previewed” error

If you are seeing the message “This block has encountered an error and cannot be previewed”, please follow the current troubleshooting flow here:

Block Errors and Editor Troubleshooting

That guide covers the main decision points for block preview failures, invalid content warnings, editor-side errors, plugin conflicts, and post-update regressions.

If the Gutenberg plugin is active, deactivate it first and test again. If you are using one of our newer block-based themes, also review LT Theme Compatibility and Post-Update Troubleshooting.