There is nothing built in to ISPF.
Some third party products might offer this (JEM, PROJCL, etc.)
I saw somewhere a shareware EDIT macro called SHOWPROC that would use the cursor location to get the PROC name and copy in the PROC as ===MSG> lines for viewing. The macro needed customization for each site to enter the possible PROCLIB dsnames. Can't find it now, though.
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