PT-Online-schema errors

FYI the link to report a bug is broken… I was going to attempt to file a bug report with online schema change… pt-online-schema-change 3.5.7

The area around that trigger is

    -- Replace single quotes in the email address
    SET @safe_email = REPLACE(NEW.Email, '''', '''''');

    -- Validate and prepare the IP address, using a default if the format is incorrect
    IF NEW.xx REGEXP '^(?:[0-9]{1,3}\\.){3}[0-9]{1,3}$' THEN
        SET valid_xx = NEW.xx;
        SET valid_xx = '';  -- Use default IP if format is incorrect
    END IF;