Delete Chatter on products ​ ​

sudo -u postgres psql

SELECT id 
FROM product_template 
WHERE default_code = 'CBM04397';

Note down the resulting id (e.g., 1234).

DELETE FROM mail_message 
WHERE model = 'product.template' AND res_id = 1234;

DELETE FROM mail_activity

WHERE res_model = 'product.template';

DELETE FROM mail_followers

WHERE res_model = 'product.template';

DELETE FROM mail_message

WHERE model = 'product.template';