Embarcadero has released patches for the RAD Studio 10.4 product.
The patches consist of a compiler patch, a general patch and a RTL patch.
These patches can be obtained with the GetIt functionality within the IDE.
In 2017, with the release of Delphi 10.2 Tokyo, Embarcadero introduced a specialized implementation of the Observer pattern into the System.Classes unit. While it has been in the wild for 9 years, it remains a "hidden" architecture for many, primarily because it serves as the invisible engine behind LiveBindings. Other than live bindings, you can also use the Observer pattern as a way to update component settings to the Windows registry, an .ini file, or persist it elsewhere.
System.Classes