As of #11466 we no longer have any logic to prevent a user from opening a wallet twice in two instances simultaneously. Not only could this break BDB (without the -privdb=false option, which I have really no idea why we even have a tuneable option for that), but we certainly don't have logic to handle such a case gracefully. It was noted in the original PR's description, but somehow was never followed up on before merge.
{
    
#ifdef _MSC_VER
    
    _CrtSetReportMode(_CRT_WARN, _CRTDBG_MODE_FILE);
    _CrtSetReportFile(_CRT_WARN, CreateFileA("NUL", GENERIC_WRITE, 0, nullptr, OPEN_EXISTING, 0, 0));
    
    _set_abort_behavior(0, _WRITE_ABORT_MSG | _CALL_REPORTFAULT);
#endif
#ifdef WIN32
    
    
    
#ifndef PROCESS_DEP_ENABLE
    
    
#define PROCESS_DEP_ENABLE 0x00000001
#endif
    typedef BOOL (WINAPI *PSETPROCDEPPOL)(DWORD);
    PSETPROCDEPPOL setProcDEPPol = (PSETPROCDEPPOL)GetProcAddress(GetModuleHandleA("Kernel32.dll"), "SetProcessDEPPolicy");
    if (setProcDEPPol != nullptr) setProcDEPPol(PROCESS_DEP_ENABLE);
#endif
    if (!SetupNetworking())
        return InitError("Initializing networking failed");
#ifndef WIN32
    if (!gArgs.GetBoolArg("-sysperms", false)) {