Debug Behaviour Mapping: possibility to choose alternative mapping mode if "source" fails

Context: see Preferences ? EGL ? Debug ? Debug Behaviour Mapping (Called Program)
During debug, when a call statement is about to be executed, the debugger checks the debug behaviour mapping to decide how to resolve the called program.
When ?source? is the mapping mode that fits the program, the following is the implemented:
1. The debugger looks for the EGL Source code of the called program. If the EGL Source is found, this source code will be loaded in the debugger.
2. If the source is not found, the debugger suggests to look for the ?generated? (mapping mode) instead.

Our RFE is that we can choose what the mapping mode for ?2. ? is.
We're eager to implement your IMS Debug solution, but we'll need this behaviour in order to do so:
1. The debugger looks for the EGL Source code of the called program. If the EGL Source is found, this source code will be loaded in the debugger.
2. If the source is not found, the debugger suggests to look for the ?IMS Debug? (mapping mode) instead.



Suggestions on implementation
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1. An implementation could be a dropdown list ?Alternative mapping mode when the EGL Source code cannot be found?. This would have at least 2 available options:
? Generated
? IMS Debug


2. Another implementation could be extra mapping modes:
? source if present, otherwise IMS Debug
? source if present, otherwise Generated (as source is currently implemented)