Title: Block-based Widgets Editor Error
Last modified: November 9, 2022

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# Block-based Widgets Editor Error

 *  [Jenish Shrestha](https://wordpress.org/support/users/jenish11/)
 * (@jenish11)
 * [3 years, 7 months ago](https://wordpress.org/support/topic/block-based-widgets-editor-error/)
 * If a add any default blocks into the editor it throws error in console.
 * `Uncaught TypeError: Cannot read properties of undefined (reading 'blocks')`
 * Widget area was registered using register_sidebar.

Viewing 3 replies - 1 through 3 (of 3 total)

 *  Thread Starter [Jenish Shrestha](https://wordpress.org/support/users/jenish11/)
 * (@jenish11)
 * [3 years, 7 months ago](https://wordpress.org/support/topic/block-based-widgets-editor-error/#post-16180961)
 * I noticed resetting database with exact same plugins and theme activated fixes
   the problem. But I lose all my data.
 * Does anyone have any idea what’s happening?
 *  [Rolf Allard van Hagen](https://wordpress.org/support/users/ravanh/)
 * (@ravanh)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/block-based-widgets-editor-error/#post-16452518)
 * Very strange…
 * I’m running into this error on the Widgets admin page with no plugins activated,
   using (for example) Twenty Twenty or Twenty Twenty-One. The error occurs when
   trying to add any block to any widget zone and prevents me from saving the widget
   settings.
 * Tried all sorts of things (de/activating plugins, switching themes, clearing 
   my browser cache and cookies) but nothing seems to get rid of the error. There
   is NO caching going on, except PHP OPcache on the server side.
 * This is happening on a dev/test website and where I test all kind of themes, 
   plugins and plugin combinations so I really cannot say when exactly this issue
   started. But again: deactivating all plugins and switching to a default Twenty
   theme does not fix it.
 * Very, very strange…
 *  [Rolf Allard van Hagen](https://wordpress.org/support/users/ravanh/)
 * (@ravanh)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/block-based-widgets-editor-error/#post-16455607)
 * Update: it occurred to me that there might be some residual stuff in the Inactive
   widgets. However, as long as the error was there, the Inactive Widgets zone appeared
   empty (I was sure it wasn’t).
 * So I switched to a theme that does not support the block based widgets and uses
   the classic widgets interface. In the classic interface there is a button Clear
   Inactive Widgets…
 * Then switched back to the block theme and I could edit the widgets again 🙂

Viewing 3 replies - 1 through 3 (of 3 total)

The topic ‘Block-based Widgets Editor Error’ is closed to new replies.

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 4 replies
 * 2 participants
 * Last reply from: [Rolf Allard van Hagen](https://wordpress.org/support/users/ravanh/)
 * Last activity: [3 years, 4 months ago](https://wordpress.org/support/topic/block-based-widgets-editor-error/#post-16455607)
 * Status: not resolved

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