diff --git a/src/plugins/diffeditor/diffeditordocument.cpp b/src/plugins/diffeditor/diffeditordocument.cpp
index 529dac382e8..f68143bbbaf 100644
--- a/src/plugins/diffeditor/diffeditordocument.cpp
+++ b/src/plugins/diffeditor/diffeditordocument.cpp
@@ -76,6 +76,14 @@ DiffEditorController *DiffEditorDocument::controller() const
     return m_controller;
 }
 
+static void appendRow(ChunkData *chunk, const RowData &row)
+{
+    const bool isSeparator = row.leftLine.textLineType == TextLineData::Separator
+            && row.rightLine.textLineType == TextLineData::Separator;
+    if (!isSeparator)
+        chunk->rows.append(row);
+}
+
 ChunkData DiffEditorDocument::filterChunk(const ChunkData &data,
                                           const ChunkSelection &selection, bool revert)
 {
@@ -83,27 +91,47 @@ ChunkData DiffEditorDocument::filterChunk(const ChunkData &data,
         return data;
 
     ChunkData chunk(data);
-    for (int i = 0; i < chunk.rows.count(); ++i) {
-        RowData &row = chunk.rows[i];
-        if (i < selection.startRow || i >= selection.startRow + selection.selectedRowsCount) {
+    chunk.rows.clear();
+    for (int i = 0; i < data.rows.count(); ++i) {
+        RowData row = data.rows[i];
+        const bool isLeftSelected = selection.leftSelection.contains(i);
+        const bool isRightSelected = selection.rightSelection.contains(i);
+
+        if (isLeftSelected || isRightSelected) {
+            if (row.equal || (isLeftSelected && isRightSelected)) {
+                appendRow(&chunk, row);
+            } else if (isLeftSelected) {
+                RowData newRow = row;
+
+                row.rightLine = TextLineData(TextLineData::Separator);
+                appendRow(&chunk, row);
+
+                if (revert) {
+                    newRow.leftLine = newRow.rightLine;
+                    newRow.equal = true;
+                    appendRow(&chunk, newRow);
+                }
+            } else { // isRightSelected
+                if (!revert) {
+                    RowData newRow = row;
+                    newRow.rightLine = newRow.leftLine;
+                    newRow.equal = true;
+                    appendRow(&chunk, newRow);
+                }
+
+                row.leftLine = TextLineData(TextLineData::Separator);
+                appendRow(&chunk, row);
+            }
+        } else {
             if (revert)
                 row.leftLine = row.rightLine;
             else
                 row.rightLine = row.leftLine;
             row.equal = true;
+            appendRow(&chunk, row);
         }
     }
 
-    for (int i = 0; i < chunk.rows.count(); ) {
-        const RowData &row = chunk.rows[i];
-        const bool isSeparator = row.leftLine.textLineType == TextLineData::Separator
-                && row.rightLine.textLineType == TextLineData::Separator;
-        if (isSeparator)
-            chunk.rows.removeAt(i);
-        else
-            ++i;
-    }
-
     return chunk;
 }
 
diff --git a/src/plugins/diffeditor/diffeditorplugin.cpp b/src/plugins/diffeditor/diffeditorplugin.cpp
index 652c6e9d14f..a4372ae0b1e 100644
--- a/src/plugins/diffeditor/diffeditorplugin.cpp
+++ b/src/plugins/diffeditor/diffeditorplugin.cpp
@@ -1431,11 +1431,14 @@ void DiffEditor::Internal::DiffEditorPlugin::testReadPatch()
     }
 }
 
+using ListOfStringPairs = QList<QPair<QString, QString>>;
+
 void DiffEditor::Internal::DiffEditorPlugin::testFilterPatch_data()
 {
     QTest::addColumn<ChunkData>("chunk");
-    QTest::addColumn<QStringList>("rightLines");
+    QTest::addColumn<ListOfStringPairs>("rows");
     QTest::addColumn<ChunkSelection>("selection");
+    QTest::addColumn<bool>("revert");
 
     auto createChunk = []() {
         ChunkData chunk;
@@ -1455,29 +1458,29 @@ void DiffEditor::Internal::DiffEditorPlugin::testFilterPatch_data()
         chunk->rows.append(row);
     };
     ChunkData chunk;
-    QStringList rightLines;
+    ListOfStringPairs rows;
 
     chunk = createChunk();
     appendRow(&chunk, "A", "A"); // 50
     appendRow(&chunk, "",  "B"); // 51 +
     appendRow(&chunk, "C", "C"); // 52
-    rightLines = QStringList {
-        "A",
-        "B",
-        "C"
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"", "B"},
+        {"C", "C"}
     };
-    QTest::newRow("one added") << chunk << rightLines << ChunkSelection();
+    QTest::newRow("one added") << chunk << rows << ChunkSelection() << false;
 
     chunk = createChunk();
     appendRow(&chunk, "A", "A"); // 50
     appendRow(&chunk, "B", "");  // 51 -
     appendRow(&chunk, "C", "C"); // 52
-    rightLines = QStringList {
-        "A",
-        "",
-        "C"
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"B", ""},
+        {"C", "C"}
     };
-    QTest::newRow("one removed") << chunk << rightLines << ChunkSelection();
+    QTest::newRow("one removed") << chunk << rows << ChunkSelection() << false;
 
     chunk = createChunk();
     appendRow(&chunk, "A", "A"); // 50
@@ -1486,26 +1489,26 @@ void DiffEditor::Internal::DiffEditorPlugin::testFilterPatch_data()
     appendRow(&chunk, "",  "D"); // 53 +
     appendRow(&chunk, "",  "E"); // 54
     appendRow(&chunk, "F", "F"); // 55
-    rightLines = QStringList {
-        "A",
-        "C",
-        "D",
-        "F",
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"", "C"},
+        {"", "D"},
+        {"F", "F"}
     };
-    QTest::newRow("stage selected added") << chunk << rightLines << ChunkSelection(2, 2);
+    QTest::newRow("stage selected added") << chunk << rows << ChunkSelection({2, 3}, {2, 3}) << false;
 
     chunk = createChunk();
     appendRow(&chunk, "A", "A"); // 50
     appendRow(&chunk, "",  "B"); // 51 +
     appendRow(&chunk, "C", "D"); // 52
     appendRow(&chunk, "E", "E"); // 53
-    rightLines = QStringList {
-            "A",
-            "B",
-            "C",
-            "E",
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"", "B"},
+        {"C", "C"},
+        {"E", "E"}
     };
-    QTest::newRow("stage selected added keep changed") << chunk << rightLines << ChunkSelection(1, 1);
+    QTest::newRow("stage selected added keep changed") << chunk << rows << ChunkSelection({1}, {1}) << false;
 
     chunk = createChunk();
     appendRow(&chunk, "A", "A"); // 50
@@ -1514,15 +1517,15 @@ void DiffEditor::Internal::DiffEditorPlugin::testFilterPatch_data()
     appendRow(&chunk, "D", "");  // 53 -
     appendRow(&chunk, "E", "");  // 54
     appendRow(&chunk, "F", "F"); // 55
-    rightLines = QStringList {
-            "A",
-            "B",
-            "",
-            "",
-            "E",
-            "F",
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"B", "B"},
+        {"C", ""},
+        {"D", ""},
+        {"E", "E"},
+        {"F", "F"}
     };
-    QTest::newRow("stage selected removed") << chunk << rightLines << ChunkSelection(2, 2);
+    QTest::newRow("stage selected removed") << chunk << rows << ChunkSelection({2, 3}, {2, 3}) << false;
 
     chunk = createChunk();
     appendRow(&chunk, "A", "A"); // 50
@@ -1531,37 +1534,132 @@ void DiffEditor::Internal::DiffEditorPlugin::testFilterPatch_data()
     appendRow(&chunk, "",  "D"); // 53 +
     appendRow(&chunk, "",  "E"); // 54
     appendRow(&chunk, "F", "F"); // 55
-    rightLines = QStringList {
-            "A",
-            "B",
-            "",
-            "D",
-            "F",
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"B", "B"},
+        {"C", ""},
+        {"", "D"},
+        {"F", "F"}
     };
-    QTest::newRow("stage selected added/removed") << chunk << rightLines << ChunkSelection(2, 2);
+    QTest::newRow("stage selected added/removed") << chunk << rows << ChunkSelection({2, 3}, {2, 3}) << false;
 
     chunk = createChunk();
     appendRow(&chunk, "A", "A"); // 50
     appendRow(&chunk, "B", "C"); // 51 -/+
     appendRow(&chunk, "D", "D"); // 52
-    rightLines = QStringList {
-            "A",
-            "C",
-            "D",
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"B", "C"},
+        {"D", "D"}
     };
-    QTest::newRow("stage modified row") << chunk << rightLines << ChunkSelection(1, 1);
+    QTest::newRow("stage modified row") << chunk << rows << ChunkSelection({1}, {1}) << false;
+
+    chunk = createChunk();
+    appendRow(&chunk, "A", "A"); // 50
+    appendRow(&chunk, "B", "C"); // 51 -/+
+    appendRow(&chunk, "D", "D"); // 52
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"B", "C"},
+        {"D", "D"}
+    };
+    QTest::newRow("stage modified and unmodified rows") << chunk << rows << ChunkSelection({0, 1, 2}, {0, 1, 2}) << false;
+
+    chunk = createChunk();
+    appendRow(&chunk, "A", "A"); // 50
+    appendRow(&chunk, "B", "C"); // 51 -/+
+    appendRow(&chunk, "D", "D"); // 52
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"B", "C"},
+        {"D", "D"}
+    };
+    QTest::newRow("stage unmodified left rows") << chunk << rows << ChunkSelection({0, 1, 2}, {1}) << false;
+
+    chunk = createChunk();
+    appendRow(&chunk, "A", "A"); // 50
+    appendRow(&chunk, "B", "C"); // 51 -/+
+    appendRow(&chunk, "D", "D"); // 52
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"B", "C"},
+        {"D", "D"}
+    };
+    QTest::newRow("stage unmodified right rows") << chunk << rows << ChunkSelection({1}, {0, 1, 2}) << false;
+
+    chunk = createChunk();
+    appendRow(&chunk, "A", "A"); // 50
+    appendRow(&chunk, "B", "C"); // 51 -/+
+    appendRow(&chunk, "D", "D"); // 52
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"B", ""},
+        {"D", "D"}
+    };
+    QTest::newRow("stage left only") << chunk << rows << ChunkSelection({1}, {}) << false;
+
+    chunk = createChunk();
+    appendRow(&chunk, "A", "A"); // 50
+    appendRow(&chunk, "B", "C"); // 51 -/+
+    appendRow(&chunk, "D", "D"); // 52
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"B", "B"},
+        {"", "C"},
+        {"D", "D"}
+    };
+    QTest::newRow("stage right only") << chunk << rows << ChunkSelection({}, {1}) << false;
+
+    chunk = createChunk();
+    appendRow(&chunk, "A", "A"); // 50
+    appendRow(&chunk, "B", "C"); // 51 -/+
+    appendRow(&chunk, "D", "D"); // 52
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"B", "C"},
+        {"D", "D"}
+    };
+    QTest::newRow("stage modified row and revert") << chunk << rows << ChunkSelection({1}, {1}) << true;
+
+    chunk = createChunk();
+    appendRow(&chunk, "A", "A"); // 50
+    appendRow(&chunk, "B", "C"); // 51 -/+
+    appendRow(&chunk, "D", "D"); // 52
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"B", ""},
+        {"C", "C"},
+        {"D", "D"}
+    };
+    // symmetric to: "stage right only"
+    QTest::newRow("stage left only and revert") << chunk << rows << ChunkSelection({1}, {}) << true;
+
+    chunk = createChunk();
+    appendRow(&chunk, "A", "A"); // 50
+    appendRow(&chunk, "B", "C"); // 51 -/+
+    appendRow(&chunk, "D", "D"); // 52
+    rows = ListOfStringPairs {
+        {"A", "A"},
+        {"", "C"},
+        {"D", "D"}
+    };
+    // symmetric to: "stage left only"
+    QTest::newRow("stage right only and revert") << chunk << rows << ChunkSelection({}, {1}) << true;
+
 }
 
 void DiffEditor::Internal::DiffEditorPlugin::testFilterPatch()
 {
     QFETCH(ChunkData, chunk);
-    QFETCH(QStringList, rightLines);
+    QFETCH(ListOfStringPairs, rows);
     QFETCH(ChunkSelection, selection);
+    QFETCH(bool, revert);
 
-    ChunkData result = DiffEditorDocument::filterChunk(chunk, selection, false);
-    QCOMPARE(result.rows.size(), rightLines.size());
-    for (int i = 0; i < rightLines.size(); ++i) {
-        QCOMPARE(result.rows.at(i).rightLine.text, rightLines.at(i));
+    const ChunkData result = DiffEditorDocument::filterChunk(chunk, selection, revert);
+    QCOMPARE(result.rows.size(), rows.size());
+    for (int i = 0; i < rows.size(); ++i) {
+        QCOMPARE(result.rows.at(i).leftLine.text, rows.at(i).first);
+        QCOMPARE(result.rows.at(i).rightLine.text, rows.at(i).second);
     }
 }
 
diff --git a/src/plugins/diffeditor/diffutils.cpp b/src/plugins/diffeditor/diffutils.cpp
index e233173629f..6c024ebd01a 100644
--- a/src/plugins/diffeditor/diffutils.cpp
+++ b/src/plugins/diffeditor/diffutils.cpp
@@ -26,6 +26,7 @@
 #include "diffutils.h"
 
 #include <texteditor/fontsettings.h>
+#include <utils/algorithm.h>
 #include <utils/differ.h>
 
 #include <QFutureInterfaceBase>
@@ -37,6 +38,11 @@ using namespace Utils;
 
 namespace DiffEditor {
 
+int ChunkSelection::selectedRowsCount() const
+{
+    return Utils::toSet(leftSelection).unite(Utils::toSet(rightSelection)).count();
+}
+
 static QList<TextLineData> assemblyRows(const QList<TextLineData> &lines,
                                         const QMap<int, int> &lineSpans)
 {
diff --git a/src/plugins/diffeditor/diffutils.h b/src/plugins/diffeditor/diffutils.h
index 47ae8c126ac..d4f05af7f7d 100644
--- a/src/plugins/diffeditor/diffutils.h
+++ b/src/plugins/diffeditor/diffutils.h
@@ -102,10 +102,12 @@ public:
 class DIFFEDITOR_EXPORT ChunkSelection {
 public:
     ChunkSelection() {}
-    ChunkSelection(int s, int c) : startRow(s), selectedRowsCount(c) {}
-    bool isNull() const { return selectedRowsCount <= 0; }
-    int startRow = -1;
-    int selectedRowsCount = 0;
+    ChunkSelection(const QList<int> &left, const QList<int> &right)
+        : leftSelection(left), rightSelection(right) {}
+    bool isNull() const { return leftSelection.isEmpty() && rightSelection.isEmpty(); }
+    int selectedRowsCount() const;
+    QList<int> leftSelection;
+    QList<int> rightSelection;
 };
 
 class DIFFEDITOR_EXPORT FileData {
diff --git a/src/plugins/diffeditor/sidebysidediffeditorwidget.cpp b/src/plugins/diffeditor/sidebysidediffeditorwidget.cpp
index ffe4b2bc14f..274241d4265 100644
--- a/src/plugins/diffeditor/sidebysidediffeditorwidget.cpp
+++ b/src/plugins/diffeditor/sidebysidediffeditorwidget.cpp
@@ -512,7 +512,11 @@ void SideDiffEditorWidget::contextMenuEvent(QContextMenuEvent *e)
             ? chunkRowForBlockNumber(endBlockNumber)
             : chunkRowsCountForBlockNumber(blockNumber);
 
-    const ChunkSelection selection(selectionStart, selectionEnd - selectionStart + 1);
+    QList<int> rows;
+    for (int i = selectionStart; i <= selectionEnd; ++i)
+        rows.append(i);
+
+    const ChunkSelection selection(rows, rows);
 
     emit contextMenuRequested(menu, fileIndexForBlockNumber(blockNumber),
                               chunkIndexForBlockNumber(blockNumber),
diff --git a/src/plugins/diffeditor/unifieddiffeditorwidget.cpp b/src/plugins/diffeditor/unifieddiffeditorwidget.cpp
index a383a55c15f..f5ef0ad8eef 100644
--- a/src/plugins/diffeditor/unifieddiffeditorwidget.cpp
+++ b/src/plugins/diffeditor/unifieddiffeditorwidget.cpp
@@ -194,8 +194,7 @@ void UnifiedDiffEditorWidget::contextMenuEvent(QContextMenuEvent *e)
 
     const ChunkData chunkData = m_controller.chunkData(fileIndex, chunkIndex);
 
-    int selectionStart = -1;
-    int selectionEnd = -1;
+    QList<int> leftSelection, rightSelection;
 
     for (int i = startBlockNumber; i <= endBlockNumber; ++i) {
         const int currentFileIndex = fileIndexForBlockNumber(i);
@@ -214,18 +213,14 @@ void UnifiedDiffEditorWidget::contextMenuEvent(QContextMenuEvent *e)
 
         const int leftRow = m_leftLineNumbers.value(i, qMakePair(-1, -1)).second;
         const int rightRow = m_rightLineNumbers.value(i, qMakePair(-1, -1)).second;
-        const int row = leftRow >= 0 ? leftRow : rightRow;
 
-        if (row < 0)
-            continue;
-
-        if (selectionStart < 0 || selectionStart > row)
-            selectionStart = row;
-        if (selectionEnd < 0 || selectionEnd < row)
-            selectionEnd = row;
+        if (leftRow >= 0)
+            leftSelection.append(leftRow);
+        if (rightRow >= 0)
+            rightSelection.append(rightRow);
     }
 
-    const ChunkSelection selection(selectionStart, selectionEnd - selectionStart + 1);
+    const ChunkSelection selection(leftSelection, rightSelection);
 
     addContextMenuActions(menu, fileIndexForBlockNumber(blockNumber),
                           chunkIndexForBlockNumber(blockNumber), selection);
diff --git a/src/plugins/git/gitclient.cpp b/src/plugins/git/gitclient.cpp
index c4758d64cb8..74a05760ddc 100644
--- a/src/plugins/git/gitclient.cpp
+++ b/src/plugins/git/gitclient.cpp
@@ -875,7 +875,7 @@ void GitClient::chunkActionsRequested(QMenu *menu, int fileIndex, int chunkIndex
         stageChunk(diffController, fileIndex, chunkIndex,
                    DiffEditorController::NoOption, DiffEditor::ChunkSelection());
     });
-    QAction *stageLinesAction = menu->addAction(tr("Stage %n Line(s)", "", selection.selectedRowsCount));
+    QAction *stageLinesAction = menu->addAction(tr("Stage Selection (%n Lines)", "", selection.selectedRowsCount()));
     connect(stageLinesAction, &QAction::triggered, this,
             [stageChunk, diffController, fileIndex, chunkIndex, selection]() {
         stageChunk(diffController, fileIndex, chunkIndex,
@@ -887,7 +887,7 @@ void GitClient::chunkActionsRequested(QMenu *menu, int fileIndex, int chunkIndex
         stageChunk(diffController, fileIndex, chunkIndex,
                    DiffEditorController::Revert, DiffEditor::ChunkSelection());
     });
-    QAction *unstageLinesAction = menu->addAction(tr("Unstage %n Line(s)", "", selection.selectedRowsCount));
+    QAction *unstageLinesAction = menu->addAction(tr("Unstage Selection (%n Lines)", "", selection.selectedRowsCount()));
     connect(unstageLinesAction, &QAction::triggered, this,
             [stageChunk, diffController, fileIndex, chunkIndex, selection]() {
         stageChunk(diffController, fileIndex, chunkIndex,