Error – Mage2ReviewDetail: Detail cannot be blank.

Hi there,

Message: Mage2ReviewDetail: Detail cannot be blank.

That issue because your M1’s database has some records with bad data in the value of the review_detail.detail field.
To handle for that, you could do with steps as followings:
+ Step 1: Open the php file at path: pub/ub-tool/protected/controllers/Step8Controller.php
and find to the code line:

if (!$reviewDetail2->save()) {

and replace it by code lines:

if (empty($reviewDetail2->detail)) {
    $reviewDetail2->detail = 'N/A';
}
if (!$reviewDetail2->save()) {

Once done, you could continue with data migration in the step #8 of our tool.
Regards,
Mall.