Multiline block quotes does not respect new lines

Summary

When using markdown I've noticed that block quotes both normal and multiline do not behave well with newlines.

Steps to reproduce

For example, the expectation would be that this block would respect new lines:

> asdasd
>
> asdsad
> asdasd
>
> asdsad

However, this is the result:

asdasd

asdsad asdasd

asdsad

And this is yet again with multiline

asdasd

asdsad asdasd

asdsad

One would think that, perhaps, adding two spaces might fix the problem, however, this:

> asdasd  
>  
> asdsad  
> asdasd  
>  
> asdsad  

>>>
asdasd  
  
asdsad  
asdasd  
  
asdsad  
>>>

Results in this:

asdasd

asdsad
asdasd

asdsad

asdasd

asdsad
asdasd

asdsad

I found this problem while trying to migrate a large Bugzilla (bugzilla.gnome.org) instance over to GitLab and making sure that the original text is formatted as originally written. One workaround would be to use code blocks to respect formatting, but the styling would make it really odd to follow.