javascript/DumpProp is a SAP Parameter attribute which is used to control CL_JAVA_SCRIPT: Pattern for display of global Object information. This is available within R/3 SAP systems depending on the version and release level.
Below is the standard documentation available and a few details of the attributes values .
In the traces (see javascript/DumpProp) of class CL_JAVA_Script, it is
possible to log properties of the global object beginning with trace
level 10. The output can be configured using a name template so that
individual subobjects are included in the log by specifying their name:
..
Output of global object <(><<)>Prop.Name>: If the global object has a
property of this name and is also an object, this appears in the log.
Note
The global object is logged almost every time a method is called.
Therefore, outputting properties of global objects causes the log file
to grow much more rapidly.
See SAP Parameter Documentation for full SAP documentation for this profile parameter.