With Dynamics 365 Business Central online, there are performance considerations that need to be taken into account.
Currently, both Word and RDL built-in layouts are rendered in the same application domain process when they run with SAVEASPDF or SAVEAS statements.
Since RDL layouts might enable some external code artifacts that may potentially affect data within the same application domain, it has been decided to run every custom RDL report layout in isolated mode. It's worth noticing that if you develop a report and declare DefaultLayout as RDL and the RDLLayout property, this is considered a built-in layout and should render in the same application domain.
Word layouts, no matter whether they are built-in or custom-made, do not run in isolation.
Enabling application domain isolation for custom RDL layouts provides a...
