When copying code snippets from confluence and pasting it on Jira comments, the Visual mode is misleading

Issue Summary

When copy/pasting code snippets from Confluence into Jira comments, formatting is lost even though Visual mode shows that the formatting is intact. 

This is reproducible on Data Center: (yes) / (no) - Yes

Steps to Reproduce

1. Copy a code snippet from a confluence page like in the following screenshot.
2. Now, paste it onto a Jira comment and check on Visual mode. The formatting seems to stay intact like in the screenshot below.
3. Now, switch to Text mode and you can see that the formatting is not in place.
4. Now, if the user hits Add comment, the comment gets added but it loses all the formatting.

Expected Results

The formatting should stay intact or it should show that the formatting is not there in the visual mode itself. 

Actual Results

Formatting is showing as intact on Visual mode, however the formatting doesn't exist. 

Workaround

Workaround is to switch to Text mode to confirm whether the formatting is intact and if not, add the formatting before adding the comment.