This is a common issue that was noted in X 6.3 and Cornerstone 3.3. There is more points noted at the release of those versions so I’d recommend that you read our release notes in our News page at https://theme.co/apex/forum/t/news-archive/24.
The solution to the issue is:
Please ensure Legacy X Integration is enabled before editing your Visual Composer built pages. Otherwise, your content will be wrapped in a Visual Composer Text Block element like in the video below.