I have had a personal/custom theme named "Chameleon" for over 1 year. As of yesterday, I get a notification in Wordpress to update it to the latest version. Out of curiosity, I clicked it (knowing it was not my update).
Wordpress replaced my theme with a Wordpress.org theme named "Chameleon".
I have googled this issue, and it appears Wordpress has no intention of fixing this ridiculous bug. The issue seems to have been brought up 9 years ago. I do not know how this has only become apparent now. I have been using creating Wordpress sites for clients for 9 years and never ever seen anything like this.
Does anyone know how to fix this?
Is there a function I can add that stop Wordpress looking for an update on Wordpress.org for just my custom themes?
A fix like changing the name in the style.css and folder is not going to cut it.
Try in functions.php:
//Disable automatic WordPress theme updates
add_filter( 'auto_update_theme', '__return_false' );
Or All updates in your wp-config.php file:
define( 'AUTOMATIC_UPDATER_DISABLED', true );
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Also you can try this plugin - Disable All WordPress Updates. Inside it chose option "Disable All Theme Updates".