Title: Javascript error on Child Theme
Last modified: March 7, 2019

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# Javascript error on Child Theme

 *  [mjbehrii](https://wordpress.org/support/users/mjbehrii/)
 * (@mjbehrii)
 * [7 years, 2 months ago](https://wordpress.org/support/topic/javascript-error-on-child-theme/)
 * Created a child theme.
 * I’m getting these errors:
 * priority-menu.js:47 Uncaught TypeError: Failed to execute ‘insertBefore’ on ‘
   Node’: parameter 1 is not of type ‘Node’.
    at prependElement (priority-menu.js:
   47) at updateNavigationMenu (priority-menu.js:128) at updateNavigationMenu (priority-
   menu.js:149) at updateNavigationMenu (priority-menu.js:149) at updateNavigationMenu(
   priority-menu.js:149) at updateNavigationMenu (priority-menu.js:149) at updateNavigationMenu(
   priority-menu.js:149) at updateNavigationMenu (priority-menu.js:149) at updateNavigationMenu(
   priority-menu.js:149) at updateNavigationMenu (priority-menu.js:149)
 * priority-menu.js:47 Uncaught TypeError: Failed to execute ‘insertBefore’ on ‘
   Node’: parameter 1 is not of type ‘Node’.
    at prependElement (priority-menu.js:
   47) at updateNavigationMenu (priority-menu.js:128) at HTMLDocument.<anonymous
   > (priority-menu.js:158)
 * prependElement @ priority-menu.js:47
    updateNavigationMenu @ priority-menu.js:
   128 (anonymous) @ priority-menu.js:158 priority-menu.js:47 Uncaught TypeError:
   Failed to execute ‘insertBefore’ on ‘Node’: parameter 1 is not of type ‘Node’.
   at prependElement (priority-menu.js:47) at updateNavigationMenu (priority-menu.
   js:128) at priority-menu.js:205
 * priority-menu.js:47 Uncaught TypeError: Failed to execute ‘insertBefore’ on ‘
   Node’: parameter 1 is not of type ‘Node’.
    at prependElement (priority-menu.js:
   47) at updateNavigationMenu (priority-menu.js:128) at priority-menu.js:190

Viewing 6 replies - 1 through 6 (of 6 total)

 *  [Andrew Nevins](https://wordpress.org/support/users/anevins/)
 * (@anevins)
 * WCLDN 2018 Contributor | Volunteer support
 * [7 years, 2 months ago](https://wordpress.org/support/topic/javascript-error-on-child-theme/#post-11288476)
 * We’ll need to see your site
 *  [Zen777](https://wordpress.org/support/users/markbanf/)
 * (@markbanf)
 * [7 years, 1 month ago](https://wordpress.org/support/topic/javascript-error-on-child-theme/#post-11416529)
 * Hi,
 * I am also getting this error when I switch to mobile.
 * [https://gardener.markbanf.co.uk/](https://gardener.markbanf.co.uk/)
 * I created a child theme of Twenty Nineteen.
 * The menu seems to work but it’s a bit worrying!
 *  [Andrew Nevins](https://wordpress.org/support/users/anevins/)
 * (@anevins)
 * WCLDN 2018 Contributor | Volunteer support
 * [7 years, 1 month ago](https://wordpress.org/support/topic/javascript-error-on-child-theme/#post-11433213)
 * [@markbanf](https://wordpress.org/support/users/markbanf/), Make sure to open
   a new thread: [https://wordpress.org/support/theme/twentynineteen/#new-post](https://wordpress.org/support/theme/twentynineteen/#new-post)
 *  [Andrew Nevins](https://wordpress.org/support/users/anevins/)
 * (@anevins)
 * WCLDN 2018 Contributor | Volunteer support
 * [7 years, 1 month ago](https://wordpress.org/support/topic/javascript-error-on-child-theme/#post-11433882)
 * Looks like there’s an issue with the JS that populates the ‘more’ (…) menu on
   mobile. If there are no visible menu links inside the main menu on mobile and
   all of them are inside the ‘more’ menu, then the JS will break. I do not think
   this is an issue on a Child Theme.
 *  [Andrew Nevins](https://wordpress.org/support/users/anevins/)
 * (@anevins)
 * WCLDN 2018 Contributor | Volunteer support
 * [7 years, 1 month ago](https://wordpress.org/support/topic/javascript-error-on-child-theme/#post-11434689)
 * Created a bug report: [https://core.trac.wordpress.org/ticket/46948#ticket](https://core.trac.wordpress.org/ticket/46948#ticket)
 *  [Zen777](https://wordpress.org/support/users/markbanf/)
 * (@markbanf)
 * [7 years, 1 month ago](https://wordpress.org/support/topic/javascript-error-on-child-theme/#post-11434726)
 * Thanks for all your help Andrew. Was worried it was something I had done.

Viewing 6 replies - 1 through 6 (of 6 total)

The topic ‘Javascript error on Child Theme’ is closed to new replies.

 * ![](https://i0.wp.com/themes.svn.wordpress.org/twentynineteen/3.2/screenshot.
   png)
 * Twenty Nineteen
 * [Support Threads](https://wordpress.org/support/theme/twentynineteen/)
 * [Active Topics](https://wordpress.org/support/theme/twentynineteen/active/)
 * [Unresolved Topics](https://wordpress.org/support/theme/twentynineteen/unresolved/)
 * [Reviews](https://wordpress.org/support/theme/twentynineteen/reviews/)

 * 6 replies
 * 3 participants
 * Last reply from: [Zen777](https://wordpress.org/support/users/markbanf/)
 * Last activity: [7 years, 1 month ago](https://wordpress.org/support/topic/javascript-error-on-child-theme/#post-11434726)
 * Status: not resolved