Component HTML being changed

I am using GrapesJs to define Freemarker FTL templates. I am seeking an issue when my custom component HTML has been changed after inserted into canvas or imported through Import template component using newsletter plugin.

So my original HTML content looks like:

<table>
    [#list items as item]
        <tr>
            <td>
                <div class="m-stack m-stack--ver m-stack--general">
                    Some content ${item.id}
                </div>
            </td>
        </tr>
    [/#list]
</table>

into

[#list items as item][/#list]
<table>
    <tr>
        <td>
            <div class="m-stack m-stack--ver m-stack--general">
                Some content ${item.id}
            </div>
        </td>
    </tr>
</table>

which corrupts my template.

Is there a way to bypass HTML formatting or whatever is going behind to cause this?