Title: Error at backend
Last modified: June 24, 2022

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# Error at backend

 *  Resolved [MerelB](https://wordpress.org/support/users/mableb/)
 * (@mableb)
 * [3 years, 9 months ago](https://wordpress.org/support/topic/error-at-backend-5/)
 * Hello,
 * When editing a post with customized Lazy Blocks the right side bar is loading
   very slow and I get the next error in console: _Block names must contain a namespace
   prefix, include only lowercase alphanumeric characters or dashes, and start with
   a letter. Example: my-plugin/my-custom-block_.
 * Thank you in advance.
    Mable

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Plugin Author [nK](https://wordpress.org/support/users/nko/)
 * (@nko)
 * [3 years, 9 months ago](https://wordpress.org/support/topic/error-at-backend-5/#post-15788418)
 * Hey Mable.
 * Can you provide a video with this error? I don’t know how to reproduce it locally.
 * Regards, nK.
 *  Plugin Author [nK](https://wordpress.org/support/users/nko/)
 * (@nko)
 * [3 years, 9 months ago](https://wordpress.org/support/topic/error-at-backend-5/#post-15789670)
 * If I undetstand correctly, you trying to set this name `my-plugin/my-custom-block`,
   but it is not allowed, you should use this one – `my-plugin-my-custom-block` 
   or `my-custom-block`

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘Error at backend’ is closed to new replies.

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## Tags

 * [slow backend](https://wordpress.org/support/topic-tag/slow-backend/)

 * 2 replies
 * 2 participants
 * Last reply from: [nK](https://wordpress.org/support/users/nko/)
 * Last activity: [3 years, 9 months ago](https://wordpress.org/support/topic/error-at-backend-5/#post-15789670)
 * Status: resolved