diff --git a/qucs/extsimkernels/abstractspicekernel.cpp b/qucs/extsimkernels/abstractspicekernel.cpp
index 13d490fb..03f262cb 100644
--- a/qucs/extsimkernels/abstractspicekernel.cpp
+++ b/qucs/extsimkernels/abstractspicekernel.cpp
@@ -437,7 +437,7 @@ void AbstractSpiceKernel::parseHBOutput(QString ngspice_file, QList<QList<double
                 continue;
             }
             if (lin.startsWith("Index")) { // CSV heading
-                    QStringList vars1 = lin.split(" ",qucs::SkipEmptyParts);
+                    QStringList vars1 = lin.split(" ",Qt::SkipEmptyParts);
                     vars1.removeFirst();
                     vars1.removeFirst();
                     QStringList norm_vars;
@@ -450,7 +450,7 @@ void AbstractSpiceKernel::parseHBOutput(QString ngspice_file, QList<QList<double
                     var_list.append(norm_vars);
             }
             if ((lin.contains(QRegularExpression("\\d*\\.\\d+[+-]*[eE]*[\\d]*")))) { // CSV dataline
-                QStringList vals = lin.split(" ",qucs::SkipEmptyParts);
+                QStringList vals = lin.split(" ",Qt::SkipEmptyParts);
                 QList <double> sim_point;
                 sim_point.clear();
                 for (int i=1;i<vals.count();i++) {
@@ -495,7 +495,7 @@ void AbstractSpiceKernel::parseFourierOutput(QString ngspice_file, QList<QList<d
             QString lin = ngsp_data.readLine();
             if (lin.isEmpty()) continue;
             if (lin.contains("Fourier analysis for")) {
-                QStringList tokens = lin.split(sep,qucs::SkipEmptyParts);
+                QStringList tokens = lin.split(sep,Qt::SkipEmptyParts);
                 QString var; // TODO chech
                 for (const QString& var1 : tokens) {
                     if (var1.contains('(')&&var1.contains(')')) {
@@ -717,8 +717,8 @@ void AbstractSpiceKernel::parseDC_OPoutputXY(QString xyce_file)
         QTextStream ngsp_data(&ofile);
         QStringList lines = ngsp_data.readAll().split("\n");
         if (lines.count()>=2) {
-            QStringList nods = lines.at(0).split(QRegularExpression("\\s"),qucs::SkipEmptyParts);
-            QStringList vals = lines.at(1).split(QRegularExpression("\\s"),qucs::SkipEmptyParts);
+            QStringList nods = lines.at(0).split(QRegularExpression("\\s"), Qt::SkipEmptyParts);
+            QStringList vals = lines.at(1).split(QRegularExpression("\\s"), Qt::SkipEmptyParts);
             QStringList::iterator n,v;
             for(n = nods.begin(),v = vals.begin();n!=nods.end()||v!=vals.end();n++,v++) {
                 if ((*n).startsWith("I(")) {
@@ -918,7 +918,7 @@ bool AbstractSpiceKernel::extractASCIISamples(QString &lin, QTextStream &ngsp_da
     sim_point.append(indep_val);
     for (int i=0;i<NumVars;i++) {
         if (isComplex) {
-            QStringList lst = ngsp_data.readLine().split(sep,qucs::SkipEmptyParts);
+            QStringList lst = ngsp_data.readLine().split(sep, Qt::SkipEmptyParts);
             if (lst.count()==2) {
                 double re_dep_val = lst.at(0).toDouble();  // for complex sim results
                 double im_dep_val = lst.at(1).toDouble();  // imaginary part follows
@@ -969,7 +969,7 @@ void AbstractSpiceKernel::parseXYCESTDOutput(QString std_file, QList<QList<doubl
         }
         if (lin.startsWith("End of ")) continue;
         if (lin.startsWith("Index ",Qt::CaseInsensitive)) {
-            var_list = lin.split(" ",qucs::SkipEmptyParts);
+            var_list = lin.split(" ", Qt::SkipEmptyParts);
             var_list.removeFirst(); // Drop Index
             for(int i = 0; i < var_list.count()-1; i++) {
                 QString var_re = var_list.at(i);
@@ -986,7 +986,7 @@ void AbstractSpiceKernel::parseXYCESTDOutput(QString std_file, QList<QList<doubl
             }
             continue;
         } else {
-            QStringList val_lst = lin.split(" ",qucs::SkipEmptyParts);
+            QStringList val_lst = lin.split(" ", Qt::SkipEmptyParts);
             QList<double> sim_point;
             for (int i = 1; i <= var_list.count(); i++ ) {
                 if (isComplex && i != 1) {
@@ -1074,10 +1074,10 @@ void AbstractSpiceKernel::parseResFile(QString resfile, QString &var, QStringLis
         while (!swp_data.atEnd()) {
             QString lin = swp_data.readLine();
             if (var_pattern.match(lin).hasMatch()) {
-                var = lin.split(sep,qucs::SkipEmptyParts).last();
+                var = lin.split(sep, Qt::SkipEmptyParts).last();
             }
             if (point_pattern.match(lin).hasMatch()) {
-                values.append(lin.split(sep,qucs::SkipEmptyParts).last());
+                values.append(lin.split(sep, Qt::SkipEmptyParts).last());
             }
         }
         ofile.close();
diff --git a/qucs/extsimkernels/ngspice.cpp b/qucs/extsimkernels/ngspice.cpp
index b61ae257..6169e4bf 100644
--- a/qucs/extsimkernels/ngspice.cpp
+++ b/qucs/extsimkernels/ngspice.cpp
@@ -222,7 +222,7 @@ void Ngspice::createNetlist(QTextStream &stream, int ,
             spiceNetlist.append(pc->getSpiceNetlist());
             nods = pc->Props.at(1)->Value;
             nods.replace(';', ' ');
-            outputs.append(pc->Props.at(2)->Value.split(';', qucs::SkipEmptyParts));
+            outputs.append(pc->Props.at(2)->Value.split(';', Qt::SkipEmptyParts));
 
             QRegularExpression ac_rx("^\\s*ac\\s.*", QRegularExpression::CaseInsensitiveOption);
             QRegularExpression sp_rx("^\\s*sp\\s.*", QRegularExpression::CaseInsensitiveOption);
diff --git a/qucs/extsimkernels/qucs2spice.cpp b/qucs/extsimkernels/qucs2spice.cpp
index b40143a6..033d38ee 100644
--- a/qucs/extsimkernels/qucs2spice.cpp
+++ b/qucs/extsimkernels/qucs2spice.cpp
@@ -125,7 +125,7 @@ QString qucs2spice::convert_netlist(QString netlist, bool xyce)
 QString qucs2spice::convert_rcl(const QString& line)
 {
     QString s="";
-    QStringList lst = line.split(" ",qucs::SkipEmptyParts);
+    QStringList lst = line.split(" ", Qt::SkipEmptyParts);
     QString s1 = lst.takeFirst();
     s += s1.remove(':');
     s += " " + lst.takeFirst();
@@ -141,7 +141,7 @@ QString qucs2spice::convert_header(QString line)
 {
     QString s = line;
     s.replace(".Def:",".SUBCKT ");
-    QStringList lst = s.split(' ',qucs::SkipEmptyParts);
+    QStringList lst = s.split(' ', Qt::SkipEmptyParts);
     lst.insert(2," gnd "); // ground
     s = lst.join(" ");
     s += "\n";
@@ -151,7 +151,7 @@ QString qucs2spice::convert_header(QString line)
 QString qucs2spice::convert_diode(QString line,bool xyce)
 {
     QString s="";
-    QStringList lst = line.split(" ",qucs::SkipEmptyParts);
+    QStringList lst = line.split(" ", Qt::SkipEmptyParts);
     QString name = lst.takeFirst();
     auto idx = name.indexOf(':');
     name =  name.right(name.size()-idx-1); // name
@@ -168,7 +168,7 @@ QString qucs2spice::convert_diode(QString line,bool xyce)
 QString qucs2spice::convert_mosfet(QString line, bool xyce)
 {
     QString s="";
-    QStringList lst = line.split(" ",qucs::SkipEmptyParts);
+    QStringList lst = line.split(" ", Qt::SkipEmptyParts);
     QString name = lst.takeFirst();
     auto idx = name.indexOf(':');
     name =  name.right(name.size()-idx-1); // name
@@ -210,7 +210,7 @@ QString qucs2spice::convert_mosfet(QString line, bool xyce)
 QString qucs2spice::convert_jfet(const QString& line, bool xyce)
 {
     QString s="";
-    QStringList lst = line.split(" ",qucs::SkipEmptyParts);
+    QStringList lst = line.split(" ", Qt::SkipEmptyParts);
     QString name = lst.takeFirst();
     auto idx = name.indexOf(':');
     name =  name.right(name.size()-idx-1); // name
@@ -241,7 +241,7 @@ QString qucs2spice::convert_jfet(const QString& line, bool xyce)
 QString qucs2spice::convert_bjt(const QString& line)
 {
     QString s="";
-    QStringList lst = line.split(" ",qucs::SkipEmptyParts);
+    QStringList lst = line.split(" ", Qt::SkipEmptyParts);
     QString name = lst.takeFirst();
     auto idx = name.indexOf(':');
     name =  name.right(name.size()-idx-1); // name
@@ -291,7 +291,7 @@ QString qucs2spice::convert_ccvs(const QString& line)
 
 QString qucs2spice::convert_ccs(const QString& line, bool voltage)
 {
-    QStringList lst = line.split(" ",qucs::SkipEmptyParts);
+    QStringList lst = line.split(" ", Qt::SkipEmptyParts);
     QString name = lst.takeFirst();
     auto idx = name.indexOf(':');
     name =  name.right(name.size()-idx-1); // name
@@ -323,7 +323,7 @@ QString qucs2spice::convert_vcvs(const QString& line)
 
 QString qucs2spice::convert_vcs(const QString& line,bool voltage)
 {
-    QStringList lst = line.split(" ",qucs::SkipEmptyParts);
+    QStringList lst = line.split(" ", Qt::SkipEmptyParts);
     QString name = lst.takeFirst();
     auto idx = name.indexOf(':');
     name =  name.right(name.size()-idx-1); // name
@@ -346,7 +346,7 @@ QString qucs2spice::convert_vcs(const QString& line,bool voltage)
 QString qucs2spice::convert_dc_src(const QString& line)
 {
     QString s="";
-    QStringList lst = line.split(" ",qucs::SkipEmptyParts);
+    QStringList lst = line.split(" ", Qt::SkipEmptyParts);
     QString s1 = lst.takeFirst();
     s += s1.remove(':');
     s += " " + lst.takeFirst();
@@ -361,7 +361,7 @@ QString qucs2spice::convert_dc_src(const QString& line)
 QString qucs2spice::convert_edd(const QString& line, QStringList &EqnsAndVars)
 {
     QString s="";
-    QStringList lst = line.split(" ",qucs::SkipEmptyParts);
+    QStringList lst = line.split(" ", Qt::SkipEmptyParts);
     QStringList nods;
     QString nam = lst.takeFirst().remove(':');
 
@@ -406,7 +406,7 @@ QString qucs2spice::convert_edd(const QString& line, QStringList &EqnsAndVars)
 QString qucs2spice::convert_subckt(QString line)
 {
     QString s="";
-    QStringList lst = line.split(" ",qucs::SkipEmptyParts);
+    QStringList lst = line.split(" ", Qt::SkipEmptyParts);
     QString s1 = lst.takeFirst();
     s += "X" + s1.remove("Sub:") + " gnd ";
 
@@ -440,7 +440,7 @@ QString qucs2spice::convert_subckt(QString line)
 QString qucs2spice::convert_gyrator(QString line)
 {
     QString s="";
-    QStringList lst = line.split(" ",qucs::SkipEmptyParts);
+    QStringList lst = line.split(" ", Qt::SkipEmptyParts);
     QString Name = lst.takeFirst();
     Name = Name.section(':',1,1);
     QString n1 = lst.takeFirst();
diff --git a/qucs/extsimkernels/s2spice.cpp b/qucs/extsimkernels/s2spice.cpp
index 55ca55c7..84f89fa2 100644
--- a/qucs/extsimkernels/s2spice.cpp
+++ b/qucs/extsimkernels/s2spice.cpp
@@ -109,7 +109,7 @@ bool S2Spice::convertTouchstone(QTextStream *stream)
     }
     /* input impedances */
 
-    QStringList tmp_lst = next_line.split(" ",qucs::SkipEmptyParts);
+    QStringList tmp_lst = next_line.split(" ", Qt::SkipEmptyParts);
     z[0] = tmp_lst.at(tmp_lst.count()-1).toDouble();
     for (int i = 0; i < ports; i++ ) {
         if ( a_z0 < 0 ) {  /* takes the Z value from the input file */
@@ -140,10 +140,10 @@ bool S2Spice::convertTouchstone(QTextStream *stream)
             break;
         }
         if(next_line.at(0)=='!') continue;
-        tmp_lst = next_line.split(QRegularExpression("[ \\t]"), qucs::SkipEmptyParts);
+        tmp_lst = next_line.split(QRegularExpression("[ \\t]"), Qt::SkipEmptyParts);
         if (tmp_lst.count() < 2*(ports*ports)+1) {
             while (in_stream.readLineInto(&next_line)) { // line continuation
-                auto new_items = next_line.split(QRegularExpression("[ \\t]"), qucs::SkipEmptyParts);
+                auto new_items = next_line.split(QRegularExpression("[ \\t]"), Qt::SkipEmptyParts);
                 tmp_lst.append(new_items);
                 if (tmp_lst.count() >= 2*(ports*ports)+1 ) break;
             }
diff --git a/qucs/extsimkernels/spicecompat.cpp b/qucs/extsimkernels/spicecompat.cpp
index 5b1f854d..e123d96f 100644
--- a/qucs/extsimkernels/spicecompat.cpp
+++ b/qucs/extsimkernels/spicecompat.cpp
@@ -305,7 +305,7 @@ int spicecompat::getPins(const QString &file, const QString &compname, QStringLi
         }
 
         if (subckt_header.match(lin).hasMatch()) {
-            QStringList lst2 = lin.split(sep,qucs::SkipEmptyParts);
+            QStringList lst2 = lin.split(sep, Qt::SkipEmptyParts);
             QString name = lin.section(sep,1,1,QString::SectionSkipEmpty).toLower();
             QString refname = compname.toLower();
             if (name != refname) continue;
diff --git a/qucs/main.cpp b/qucs/main.cpp
index 02186f99..c329d772 100644
--- a/qucs/main.cpp
+++ b/qucs/main.cpp
@@ -143,7 +143,7 @@ bool loadSettings()
     QucsSettings.GraphAntiAliasing = _settings::Get().item<bool>("GraphAntiAliasing");
     QucsSettings.TextAntiAliasing = _settings::Get().item<bool>("TextAntiAliasing");
     QucsSettings.fullTraceName = _settings::Get().item<bool>("fullTraceName");
-    QucsSettings.RecentDocs = _settings::Get().item<QString>("RecentDocs").split("*",qucs::SkipEmptyParts);
+    QucsSettings.RecentDocs = _settings::Get().item<QString>("RecentDocs").split("*", Qt::SkipEmptyParts);
     QucsSettings.numRecentDocs = QucsSettings.RecentDocs.count();
     QucsSettings.spiceExtensions << "*.sp" << "*.cir" << "*.spc" << "*.spi";
 
diff --git a/qucs/misc.h b/qucs/misc.h
index d6ec8cd0..5e5549bd 100644
--- a/qucs/misc.h
+++ b/qucs/misc.h
@@ -26,16 +26,6 @@
 
 #define Q_UINT32 uint32_t
 
-
-namespace qucs {
-#if QT_VERSION >= 0x050e00
-  const auto SkipEmptyParts = Qt::SkipEmptyParts;
-#else
-  const auto SkipEmptyParts = QString::SkipEmptyParts;
-#endif
-}
-
-
 class Schematic;
 
 namespace misc {
diff --git a/qucs/schematic.cpp b/qucs/schematic.cpp
index 5a3b332b..9bec4139 100644
--- a/qucs/schematic.cpp
+++ b/qucs/schematic.cpp
@@ -1810,7 +1810,7 @@ int Schematic::adjustPortNumbers()
             VInfo = VHDL_File_Info(Name, true);
 
         if (!VInfo.PortNames.isEmpty())
-            Names = VInfo.PortNames.split(",", qucs::SkipEmptyParts);
+            Names = VInfo.PortNames.split(",", Qt::SkipEmptyParts);
 
         for (pp = a_SymbolPaints.first(); pp != 0; pp = a_SymbolPaints.next())
             if (pp->Name == ".ID ") {
@@ -1818,11 +1818,11 @@ int Schematic::adjustPortNumbers()
                 id->Prefix = VInfo.EntityName.toUpper();
                 id->Parameter.clear();
                 if (!VInfo.GenNames.isEmpty())
-                    GNames = VInfo.GenNames.split(",", qucs::SkipEmptyParts);
+                    GNames = VInfo.GenNames.split(",", Qt::SkipEmptyParts);
                 if (!VInfo.GenTypes.isEmpty())
-                    GTypes = VInfo.GenTypes.split(",", qucs::SkipEmptyParts);
+                    GTypes = VInfo.GenTypes.split(",", Qt::SkipEmptyParts);
                 if (!VInfo.GenDefs.isEmpty())
-                    GDefs = VInfo.GenDefs.split(",", qucs::SkipEmptyParts);
+                    GDefs = VInfo.GenDefs.split(",", Qt::SkipEmptyParts);
                 ;
                 for (Number = 1, it = GNames.begin(); it != GNames.end(); ++it) {
                     id->Parameter.append(
@@ -1871,7 +1871,7 @@ int Schematic::adjustPortNumbers()
         else
             VInfo = Verilog_File_Info(Name, true);
         if (!VInfo.PortNames.isEmpty())
-            Names = VInfo.PortNames.split(",", qucs::SkipEmptyParts);
+            Names = VInfo.PortNames.split(",", Qt::SkipEmptyParts);
 
         for (pp = a_SymbolPaints.first(); pp != 0; pp = a_SymbolPaints.next())
             if (pp->Name == ".ID ") {
@@ -1918,7 +1918,7 @@ int Schematic::adjustPortNumbers()
             VInfo = VerilogA_File_Info(Name, true);
 
         if (!VInfo.PortNames.isEmpty())
-            Names = VInfo.PortNames.split(",", qucs::SkipEmptyParts);
+            Names = VInfo.PortNames.split(",", Qt::SkipEmptyParts);
 
         for (pp = a_SymbolPaints.first(); pp != 0; pp = a_SymbolPaints.next())
             if (pp->Name == ".ID ") {
diff --git a/qucs/schematic_file.cpp b/qucs/schematic_file.cpp
index 67163e8c..188b8439 100644
--- a/qucs/schematic_file.cpp
+++ b/qucs/schematic_file.cpp
@@ -299,7 +299,7 @@ int Schematic::savePropsJSON()
         continue;
       }
       if (line.contains("parameter")) {
-        auto tokens = line.split(QRegularExpression("[\\s=;]"),qucs::SkipEmptyParts);
+        auto tokens = line.split(QRegularExpression("[\\s=;]"), Qt::SkipEmptyParts);
         if (tokens.count() >= 4) {
           for(int ic = 0; ic <= tokens.count(); ic++) {
             if (tokens.at(ic) == "parameter") {