WordPress Importer plugin does not handle continuous line feed

I use WordPress 5.0.2 Japanese edition.
(running on Ubuntu 16.04LTS / MySQL)

I guess WordPress Importer plugin does not handle continuous line feed.

Content part of the imported XML file is as follows:

+———————————————————-+
<content:encoded><![CDATA[This is a test diary.
test
test

test2
test2

test3
test3
]]></content:encoded>
+———————————————————-+

It is stored in the table of the MySQL database as follows.

mysql> select post_content from wp_posts where id=7;
+———————————————————-+
| post_content |
+———————————————————-+
| This is a test diary.
test
test
test2
test2
test3
test3
|
+———————————————————-+

In this case, I think that it should be stored in the database as follows.

+———————————————————-+
This is a test diary.
test
test

test2
test2

test3
test3
+———————————————————-+

I think that it is a trouble or bug of the plugin.

Thank you for reading until the end.