When working with the source code listings, this is very annoying: when pasting the listings into the editor, the leading spaces would be removed and original alignment corrupt. This happens when pasting from the other applications as well as within the editor itself.
I cannot reproduce this. Please provide a minamal example.
This happens to me when the Indentation Mode in the Editor Options is set to "Indent and Unindent Automatically", when set to ignore indentation this does not occur. Not sure if bug or feature tbh...