Browser post, 'code' loses leading spaces [edited}
Indented code loses leading spaces & tabs.
In the linked thread, the attachment shows preview in editor looks ok, but the post above, first via Outlook and second via Empathy, is how it ends up.
Note extra line spacing in the first post is due to Outlook badly formatting plain-text from the entered HTML. Extra spacing in the second (Empathy) post is due to