If I have a small inline function definition in my header, that I decide to move to my source, that starts like:
	// check if there is an item for the alias 
	inline CDynamicMenuItem * CDynamicMenu::FindItem(const CString & name)
	{
		if (!this)
			return nullptr;
		// translates a given name to an nID, or returns false if not found
		auto it = m_aliases.find(name);
		if (it == m_aliases.end())
			return nullptr;
		return it->second;
	}
Then after using refactor - move to source - I'll end up with:
	DynamicMenu::CDynamicMenuItem * CDynamicMenu::FindItem(const CString & name)
	{
		if (!this)
			return nullptr;
		// translates a given name to an nID, or returns false if not found
		auto it = m_aliases.find(name);
		if (it == m_aliases.end())
			return nullptr;
		return it->second;
	}
The title comment - describing what this function is for - is gone from the header, and did not make it to the .cpp file.