diff --git a/.github/workflows/ubuntu.yml b/.github/workflows/ubuntu.yml
index 222d6c8..0053e5c 100644
--- a/.github/workflows/ubuntu.yml
+++ b/.github/workflows/ubuntu.yml
@@ -3,32 +3,6 @@ name: Ubuntu CI
 on: [push, pull_request]
 
 jobs:
-  ubuntu-20-04-build:
-
-    runs-on: ubuntu-20.04
-
-    steps:
-      - uses: actions/checkout@v3
-      - name: Get build dept.
-        run: |
-          sudo apt update
-          sudo apt install cmake qtbase5-dev libqt5svg5-dev qttools5-dev libexiv2-dev
-      - name: Build it
-        run: |
-          mkdir build
-          cd build
-          cmake ../
-          make
-          cpack -G DEB
-      - name: Try install it
-        run: |
-          cd build
-          sudo apt install ./*.deb
-      - uses: actions/upload-artifact@v3
-        with:
-          name: ubuntu-20.04-deb-package
-          path: build/*.deb
-
   ubuntu-22-04-build:
 
     runs-on: ubuntu-22.04
diff --git a/CMakeLists.txt b/CMakeLists.txt
index dbad14c..30c11df 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -24,7 +24,7 @@ else ()
 endif ()
 
 if (${QT_VERSION_MAJOR} EQUAL "5")
-    set (QT_MINIMUM_VERSION "5.10")
+    set (QT_MINIMUM_VERSION "5.15.2")
 else ()
     set (QT_MINIMUM_VERSION "6.4")
 endif ()
@@ -102,12 +102,7 @@ set (EXE_NAME ppic)
 file (GLOB PPIC_TS_FILES app/translations/*.ts)
 set (PPIC_CPP_FILES_FOR_I18N ${PPIC_CPP_FILES})
 
-if (${QT_VERSION_MAJOR} EQUAL "5")
-    # TODO: remove this when we lift our Qt5 minimum version to Qt 5.15
-    qt5_create_translation(PPIC_QM_FILES ${PPIC_CPP_FILES_FOR_I18N} ${PPIC_TS_FILES})
-else ()
-    qt_create_translation(PPIC_QM_FILES ${PPIC_CPP_FILES_FOR_I18N} ${PPIC_TS_FILES})
-endif ()
+qt_create_translation(PPIC_QM_FILES ${PPIC_CPP_FILES_FOR_I18N} ${PPIC_TS_FILES})
 
 if (WIN32)
     list(APPEND PPIC_RC_FILES assets/pineapple-pictures.rc)
@@ -140,9 +135,9 @@ if (LibExiv2_FOUND)
     )
 endif ()
 
-if (Qt5DBus_FOUND)
+if (Qt5DBus_FOUND OR Qt6DBus_FOUND)
     target_link_libraries (${EXE_NAME}
-        Qt5::DBus
+        Qt${QT_VERSION_MAJOR}::DBus
     )
     target_compile_definitions(${EXE_NAME} PRIVATE
         HAVE_QTDBUS
diff --git a/app/graphicsview.cpp b/app/graphicsview.cpp
index f4b8f60..0bff010 100644
--- a/app/graphicsview.cpp
+++ b/app/graphicsview.cpp
@@ -13,13 +13,6 @@
 #include <QImageReader>
 #include <QStyleOptionGraphicsItem>
 
-// TODO: remove this once we drop older Qt support.
-#if QT_VERSION >= QT_VERSION_CHECK(5, 13, 0)
-#define COMPAT_CONSTCOLOR constexpr
-#else
-#define COMPAT_CONSTCOLOR const
-#endif
-
 GraphicsView::GraphicsView(QWidget *parent)
     : QGraphicsView (parent)
 {
@@ -387,8 +380,8 @@ void GraphicsView::setCheckerboardEnabled(bool enabled, bool invertColor)
         QPixmap tilePixmap(0x20, 0x20);
         tilePixmap.fill(invertColor ? QColor(220, 220, 220, 170) : QColor(35, 35, 35, 170));
         QPainter tilePainter(&tilePixmap);
-        COMPAT_CONSTCOLOR QColor color(45, 45, 45, 170);
-        COMPAT_CONSTCOLOR QColor invertedColor(210, 210, 210, 170);
+        constexpr QColor color(45, 45, 45, 170);
+        constexpr QColor invertedColor(210, 210, 210, 170);
         tilePainter.fillRect(0, 0, 0x10, 0x10, invertColor ? invertedColor : color);
         tilePainter.fillRect(0x10, 0x10, 0x10, 0x10, invertColor ? invertedColor : color);
         tilePainter.end();
diff --git a/app/mainwindow.cpp b/app/mainwindow.cpp
index 7e78ae9..0897ad1 100644
--- a/app/mainwindow.cpp
+++ b/app/mainwindow.cpp
@@ -309,13 +309,9 @@ void MainWindow::mousePressEvent(QMouseEvent *event)
 void MainWindow::mouseMoveEvent(QMouseEvent *event)
 {
     if (event->buttons() & Qt::LeftButton && m_clickedOnWindow && !isMaximized()) {
-#if QT_VERSION >= QT_VERSION_CHECK(5, 15, 0)
         if (!window()->windowHandle()->startSystemMove()) {
             move(event->globalPos() - m_oldMousePos);
         }
-#else
-        move(event->globalPos() - m_oldMousePos);
-#endif // QT_VERSION >= QT_VERSION_CHECK(5, 15, 0)
         event->accept();
     }