The regression has been introduced in iTop 2.0.2 with the fix for #703 (escape HTML entities). There is no data loss: changes were correctly made and all the changes already recorded will be correctly displayed with the current fix.
The current change consists in a little rework: GetAsHTMLForHistory has been renamed DescribeChange, and it now calls oAttDef->GetAsHTMLForHistory instead of calling oAttDef->GetAsHTML, thus allowing for the factorization of the code that format the change description. AttributeSubitem does not overload DescribeChange. Rather, it simply overloads GetAsHTMLForHistory (viewing the diff may be confusing here).
SVN:trunk[3443]