<![CDATA[]]>in system.xml translate phrase not work

[PiscesThankIT]

Preconditions

php 5.6.19
Magento 2.1.2

Steps to reproduce

create a module which has system.xml
In the system.xml, I have a field:

<field id="test" translate="label comment" type="text" sortOrder="20" showInDefault="1" showInWebsite="1" showInStore="1">
                    <label>Test phrases</label>
                    <attribute type="shared">1</attribute>
                    <comment>
                    <![CDATA[This is for wq test!
                    <a href="https://developer.paypal.com/docs/classic/express-checkout/in-context/" target="_blank">here</a>.]]>
                    </comment>
</field>

I use the command to collect the phrases

i18n:collect-phrases -o "zh_Hans_CN.csv"  mymodule/dir

I get the csv file. In this file, I see:

                    This is for wq test!
                    <a href=""https://developer.paypal.com/docs/classic/express-checkout/in-context/"" target=""_blank"">here</a>.
                    ","
                    This is for wq test!
                    <a href=""https://developer.paypal.com/docs/classic/express-checkout/in-context/"" target=""_blank"">here</a>.
                    "

There is a line feed and some spaces before the phrase.
I change the second column to add some Chinese words.

                    This is for wq test!
                    <a href=""https://developer.paypal.com/docs/classic/express-checkout/in-context/"" target=""_blank"">here</a>.
                    ","
                    This is for wq test!应该看到我
                    <a href=""https://developer.paypal.com/docs/classic/express-checkout/in-context/"" target=""_blank"">here</a>.
                    "

I put this file in correct place and change the local language. Other simple phrases can be translated correctly, but the phrase in CDATA doesn't change.

Then I delete the line feed and spaces:

"This is for wq test!<a href=""https://developer.paypal.com/docs/classic/express-checkout/in-context/"" target=""_blank"">here</a>.","This is for wq test!按道理应该看到我<a href=""https://developer.paypal.com/docs/classic/express-checkout/in-context/"" target=""_blank"">here</a>."

I ran setup:upgrade to make Magento use new translation. But It still doesn't work!

Another test about translate

echo __('This is for wq 
            test!');

Just for test line feed in csv file.

Collect phrases:

"This is for wq 
            test!","This is for wq 
            test!"

change this to

"This is for wq 
            test!","This is for wq 
            test!按照道理我会出来"

It works!

[magento-engcom-team]

@PiscesThankIT, thank you for your report.
We've created internal ticket(s) MAGETWO-82525 to track progress on the issue.

[okorshenko]

The issue has been fixed in 2.2-develop branch