With OPI Probe CSS context menu, CSS user can pass PV names to an OPI so that their PV values can be displayed in an OPI.

A probe OPI is same as an ordinary OPI, except that you need to set the "PV Name" property of a PV widget to:
$(probe_pv) if the probe OPI only work for one PV;
$(probe_pv_index) if the probe OPI should work for multiple PVs. index
is the index of the PVs that are passed in. For example, the widget with $(probe_pv_0) will have
the first PV name passed in, $(probe_pv_1) will have the second PV name passed in, ...
The path of the probe OPI can be set in BOY preference page with the item Probe OPI.
If no probe OPI is set in BOY preference, a built-in probe OPI will be used.