Problem with product variatons addon


I have a problem when activating the product variations addon.
I am getting this error


Syntax error in template “tygh:/home/nokscors/www/design/themes/abt__youpitheme/templates/addons/product_variations/hooks/products/product_features.override.tpl” on line 3 “{$product = $product|fn_product_variations_merge_features}” unknown modifier ‘fn_product_variations_merge_features’

Error at
app/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_templatecompilerbase.php, line: 3


I contacted AB support, but they say:
The file abt__youpitheme/templates/addons/product_variations/hooks/products/product_features.override.tpl does not belong to our theme, it was created in the theme folders by someone else. I renamed it to old_product_features.override.tpl, but that caused a new error in /design/themes/responsive/templates/addons/product_variations/hooks/products/product_features.override.tpl (which isn’t usually placed there, so it’s a custom mod, made by someone).
Since these errors are not caused by our addons, we cannot fix it as part of a support request

I tried to find which addon was made that overrides, but can’t find it.

Do you have any suggestions?

Any help?

Thanks in advance!

Can somebody please give me some advice?

I’m afraid no one but you can know who made these changes to your installation and when.

What is your suggestion? Maybe to disable one by one, and try to find one that make these problems?

You can rename these files, clear the cache and check if it works.