Title: Undefined array key “properties”
Last modified: November 25, 2025

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# Undefined array key “properties”

 *  Resolved [mailtobb](https://wordpress.org/support/users/mailtobb/)
 * (@mailtobb)
 * [6 months ago](https://wordpress.org/support/topic/undefined-array-key-properties/)
 * Great plugin!
 * However, the newest update keeps sending error message -> Warning: Undefined 
   array key “properties” in /usr/www/users/beyersp/live/wp-content/plugins/unipixel/
   woocomm-hook-handling/hook-handlers-checkout.php on line 220
 * Thanks,
 * Bastian
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fundefined-array-key-properties%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

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

 *  Thread Starter [mailtobb](https://wordpress.org/support/users/mailtobb/)
 * (@mailtobb)
 * [6 months ago](https://wordpress.org/support/topic/undefined-array-key-properties/#post-18733427)
 * I just found out that the new version is not the problem, it’s the TikTok integration
   which I enabled yesterday. And it keeps sending errors. Disabling the TikTok 
   integration -> no errors.
 *  Plugin Author [Buildio](https://wordpress.org/support/users/buildiodev/)
 * (@buildiodev)
 * [2 months, 2 weeks ago](https://wordpress.org/support/topic/undefined-array-key-properties/#post-18845963)
 * Hi Bastian,
 * thanks again for taking the time to report both issues.
 * Good catch narrowing it down to TikTok — the `properties` key error was a naming
   inconsistency in the TikTok data pipeline that was resolved in a subsequent update.
 * The `HTTP_USER_AGENT` warning you reported separately has also been addressed,
   some visitors (bots, crawlers) don’t send a User-Agent header, which triggers
   that warning on PHP 8.0+.
 * Both fixes will be included in an upcoming version patch. Updating the plugin
   should clear both warnings. Let us know if you run into anything else.

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

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 * 2 replies
 * 2 participants
 * Last reply from: [Buildio](https://wordpress.org/support/users/buildiodev/)
 * Last activity: [2 months, 2 weeks ago](https://wordpress.org/support/topic/undefined-array-key-properties/#post-18845963)
 * Status: resolved