The debug version contains
IncludeConfFile sqldeveloper-nondebug.conf or IncludeConfFile sqldeveloper-debug.conf
which enables debug logging and Java assert processing. The assert actually blocks processing of the code you see the error in. Since developers typically run the debug version, we never see that message logged. The non-debug version contains
AddVMOption -Dsqldev.debug=true AddVMOption -ea
AddVMOption -Dide.AssertTracingDisabled=trueSo you should either ignore the error, or try to edit your conf files to suppress it. Possibly a bug should be logged, but the condition is benign.