CKEditor / Rin Editor

[snippsat]

It should be defaulted to source mode

No it dos not,and it shouldn't do either.
That would just be confusing for new user,
because CKEditor look quite different than old editor in source mode.
The old editor is was okay start in source because the look was the same.

This has nothing to do about source mode or not,it happen in both.
My guess is that there some escape problem somewhere maybe in a YourCode setup.
Test [ ] okay 1 space,gone together [] not here