Extra trailing line gets inserted to code blocks on saving

[akjir]

Describe the bug
After i reopened a saved file, the formatting of the code block is wrong. See screenshots.

To Reproduce
Steps to reproduce the behavior:

1. create a new file
2. write Text
3. combine with code block
4. save and close
5. reopen

Expected behavior
The reopened file should have the same formatting like before closing.

Screenshots

File i created:

Plain text:

After saving and reopening:

Client details:

• Windows 10 Pro 64bit
• Firefox 67.0.4 64bit
• Nextcloud 16.0.2
• Nextcloud Text 1.0.0

Edit: It seems the code block uses the blank line.