When a text field has the following changelog entry:
[
'fieldId' => 'customfield_10081',
'from' => null,
'fromString' => null,
'to' => '',
'toString' => 'lorem ipsum',
]
Then its corresponding snapshot will be mapped to a list value. This value (an array) will be then cast as a string (since it is originaly a text field) and PHP emits a TypeError.