diff --git a/core/color.h b/core/color.h
index 37281045e..3e9999e4e 100644
--- a/core/color.h
+++ b/core/color.h
@@ -7,65 +7,74 @@
 
 #include <QColor>
 
+static inline QColor makeColor(double r, double g, double b, double a = 1.0)
+{
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)  // they are just trolling us with these changes
+	return QColor::fromRgbF((float)r, (float)g, (float)b, (float)a);
+#else
+	return QColor::fromRgbF(r, g, b, a);
+#endif
+}
+
 // Greens
-#define CAMARONE1 QColor::fromRgbF(0.0, 0.4, 0.0, 1)
-#define FUNGREEN1 QColor::fromRgbF(0.0, 0.4, 0.2, 1)
-#define FUNGREEN1_HIGH_TRANS QColor::fromRgbF(0.0, 0.4, 0.2, 0.25)
-#define KILLARNEY1 QColor::fromRgbF(0.2, 0.4, 0.2, 1)
-#define APPLE1 QColor::fromRgbF(0.2, 0.6, 0.2, 1)
-#define APPLE1_MED_TRANS QColor::fromRgbF(0.2, 0.6, 0.2, 0.5)
-#define APPLE1_HIGH_TRANS QColor::fromRgbF(0.2, 0.6, 0.2, 0.25)
-#define LIMENADE1 QColor::fromRgbF(0.4, 0.8, 0.0, 1)
-#define ATLANTIS1 QColor::fromRgbF(0.4, 0.8, 0.2, 1)
-#define ATLANTIS2 QColor::fromRgbF(0.6, 0.8, 0.2, 1)
-#define RIOGRANDE1 QColor::fromRgbF(0.8, 0.8, 0.0, 1)
-#define EARLSGREEN1 QColor::fromRgbF(0.8, 0.8, 0.2, 1)
-#define FORESTGREEN1 QColor::fromRgbF(0.1, 0.5, 0.1, 1)
-#define NITROX_GREEN QColor::fromRgbF(0, 0.54, 0.375, 1)
+#define CAMARONE1 makeColor(0.0, 0.4, 0.0)
+#define FUNGREEN1 makeColor(0.0, 0.4, 0.2)
+#define FUNGREEN1_HIGH_TRANS makeColor(0.0, 0.4, 0.2, 0.25)
+#define KILLARNEY1 makeColor(0.2, 0.4, 0.2)
+#define APPLE1 makeColor(0.2, 0.6, 0.2)
+#define APPLE1_MED_TRANS makeColor(0.2, 0.6, 0.2, 0.5)
+#define APPLE1_HIGH_TRANS makeColor(0.2, 0.6, 0.2, 0.25)
+#define LIMENADE1 makeColor(0.4, 0.8, 0.0)
+#define ATLANTIS1 makeColor(0.4, 0.8, 0.2)
+#define ATLANTIS2 makeColor(0.6, 0.8, 0.2)
+#define RIOGRANDE1 makeColor(0.8, 0.8, 0.0)
+#define EARLSGREEN1 makeColor(0.8, 0.8, 0.2)
+#define FORESTGREEN1 makeColor(0.1, 0.5, 0.1)
+#define NITROX_GREEN makeColor(0, 0.54, 0.375)
 
 // Reds
-#define PERSIANRED1 QColor::fromRgbF(0.8, 0.2, 0.2, 1)
-#define TUSCANY1 QColor::fromRgbF(0.8, 0.4, 0.2, 1)
-#define PIRATEGOLD1 QColor::fromRgbF(0.8, 0.5, 0.0, 1)
-#define PIRATEGOLD1_MED_TRANS QColor::fromRgbF(0.8, 0.5, 0.0, 0.75)
-#define HOKEYPOKEY1 QColor::fromRgbF(0.8, 0.6, 0.2, 1)
-#define CINNABAR1 QColor::fromRgbF(0.9, 0.3, 0.2, 1)
-#define REDORANGE1 QColor::fromRgbF(1.0, 0.2, 0.2, 1)
-#define REDORANGE1_HIGH_TRANS QColor::fromRgbF(1.0, 0.2, 0.2, 0.25)
-#define REDORANGE1_MED_TRANS QColor::fromRgbF(1.0, 0.2, 0.2, 0.5)
-#define RED1_MED_TRANS QColor::fromRgbF(1.0, 0.0, 0.0, 0.5)
-#define RED1 QColor::fromRgbF(1.0, 0.0, 0.0, 1)
+#define PERSIANRED1 makeColor(0.8, 0.2, 0.2)
+#define TUSCANY1 makeColor(0.8, 0.4, 0.2)
+#define PIRATEGOLD1 makeColor(0.8, 0.5, 0.0)
+#define PIRATEGOLD1_MED_TRANS makeColor(0.8, 0.5, 0.0, 0.75)
+#define HOKEYPOKEY1 makeColor(0.8, 0.6, 0.2)
+#define CINNABAR1 makeColor(0.9, 0.3, 0.2)
+#define REDORANGE1 makeColor(1.0, 0.2, 0.2)
+#define REDORANGE1_HIGH_TRANS makeColor(1.0, 0.2, 0.2, 0.25)
+#define REDORANGE1_MED_TRANS makeColor(1.0, 0.2, 0.2, 0.5)
+#define RED1_MED_TRANS makeColor(1.0, 0.0, 0.0, 0.5)
+#define RED1 makeColor(1.0, 0.0, 0.0)
 
 // Monochromes
-#define BLACK1 QColor::fromRgbF(0.0, 0.0, 0.0, 1)
-#define BLACK1_LOW_TRANS QColor::fromRgbF(0.0, 0.0, 0.0, 0.75)
-#define BLACK1_HIGH_TRANS QColor::fromRgbF(0.0, 0.0, 0.0, 0.25)
-#define TUNDORA1_MED_TRANS QColor::fromRgbF(0.3, 0.3, 0.3, 0.5)
-#define MED_GRAY_HIGH_TRANS QColor::fromRgbF(0.5, 0.5, 0.5, 0.25)
-#define MERCURY1_MED_TRANS QColor::fromRgbF(0.9, 0.9, 0.9, 0.5)
-#define CONCRETE1_LOWER_TRANS QColor::fromRgbF(0.95, 0.95, 0.95, 0.9)
-#define WHITE1_MED_TRANS QColor::fromRgbF(1.0, 1.0, 1.0, 0.5)
-#define WHITE1 QColor::fromRgbF(1.0, 1.0, 1.0, 1)
+#define BLACK1 makeColor(0.0, 0.0, 0.0)
+#define BLACK1_LOW_TRANS makeColor(0.0, 0.0, 0.0, 0.75)
+#define BLACK1_HIGH_TRANS makeColor(0.0, 0.0, 0.0, 0.25)
+#define TUNDORA1_MED_TRANS makeColor(0.3, 0.3, 0.3, 0.5)
+#define MED_GRAY_HIGH_TRANS makeColor(0.5, 0.5, 0.5, 0.25)
+#define MERCURY1_MED_TRANS makeColor(0.9, 0.9, 0.9, 0.5)
+#define CONCRETE1_LOWER_TRANS makeColor(0.95, 0.95, 0.95, 0.9)
+#define WHITE1_MED_TRANS makeColor(1.0, 1.0, 1.0, 0.5)
+#define WHITE1 makeColor(1.0, 1.0, 1.0)
 
 // Blues
-#define GOVERNORBAY2 QColor::fromRgbF(0.2, 0.2, 0.7, 1)
-#define GOVERNORBAY1_MED_TRANS QColor::fromRgbF(0.2, 0.2, 0.8, 0.5)
-#define ROYALBLUE2 QColor::fromRgbF(0.2, 0.2, 0.9, 1)
-#define ROYALBLUE2_LOW_TRANS QColor::fromRgbF(0.2, 0.2, 0.9, 0.75)
-#define AIR_BLUE QColor::fromRgbF(0.25, 0.75, 1.0, 1)
-#define AIR_BLUE_TRANS QColor::fromRgbF(0.25, 0.75, 1.0, 0.5)
+#define GOVERNORBAY2 makeColor(0.2, 0.2, 0.7)
+#define GOVERNORBAY1_MED_TRANS makeColor(0.2, 0.2, 0.8, 0.5)
+#define ROYALBLUE2 makeColor(0.2, 0.2, 0.9)
+#define ROYALBLUE2_LOW_TRANS makeColor(0.2, 0.2, 0.9, 0.75)
+#define AIR_BLUE makeColor(0.25, 0.75, 1.0)
+#define AIR_BLUE_TRANS makeColor(0.25, 0.75, 1.0, 0.5)
 
 // Yellows / BROWNS
-#define SPRINGWOOD1 QColor::fromRgbF(0.95, 0.95, 0.9, 1)
-#define SPRINGWOOD1_MED_TRANS QColor::fromRgbF(0.95, 0.95, 0.9, 0.5)
-#define BROOM1_LOWER_TRANS QColor::fromRgbF(1.0, 1.0, 0.1, 0.9)
-#define PEANUT QColor::fromRgbF(0.5, 0.2, 0.1, 1.0)
-#define PEANUT_MED_TRANS QColor::fromRgbF(0.5, 0.2, 0.1, 0.5)
-#define NITROX_YELLOW QColor::fromRgbF(0.98, 0.89, 0.07, 1.0)
+#define SPRINGWOOD1 makeColor(0.95, 0.95, 0.9)
+#define SPRINGWOOD1_MED_TRANS makeColor(0.95, 0.95, 0.9, 0.5)
+#define BROOM1_LOWER_TRANS makeColor(1.0, 1.0, 0.1, 0.9)
+#define PEANUT makeColor(0.5, 0.2, 0.1)
+#define PEANUT_MED_TRANS makeColor(0.5, 0.2, 0.1, 0.5)
+#define NITROX_YELLOW makeColor(0.98, 0.89, 0.07)
 
 // Magentas
-#define MEDIUMREDVIOLET1_HIGHER_TRANS QColor::fromRgbF(0.7, 0.2, 0.7, 0.1)
-#define MAGENTA QColor::fromRgbF(1.0, 0.0, 1.0, 1.0)
+#define MEDIUMREDVIOLET1_HIGHER_TRANS makeColor(0.7, 0.2, 0.7, 0.1)
+#define MAGENTA makeColor(1.0, 0.0, 1.0)
 
 #define SAC_COLORS_START_IDX SAC_1
 #define SAC_COLORS 9
diff --git a/desktop-widgets/kmessagewidget.cpp b/desktop-widgets/kmessagewidget.cpp
index f293e7527..c64635220 100644
--- a/desktop-widgets/kmessagewidget.cpp
+++ b/desktop-widgets/kmessagewidget.cpp
@@ -250,9 +250,9 @@ KMessageWidget::MessageType KMessageWidget::messageType() const
 
 static QColor darkShade(QColor c)
 {
-    qreal contrast = 0.7; // taken from kcolorscheme for the dark shade
+    double contrast = 0.7; // taken from kcolorscheme for the dark shade
 
-    qreal darkAmount;
+    double darkAmount;
     if (c.lightnessF() < 0.006) { /* too dark */
         darkAmount = 0.02 + 0.40 * contrast;
     } else if (c.lightnessF() > 0.93) { /* too bright */
@@ -261,9 +261,9 @@ static QColor darkShade(QColor c)
         darkAmount = (-c.lightnessF()) * (0.55 + contrast * 0.35);
     }
 
-    qreal v = c.lightnessF() + darkAmount;
+    double v = c.lightnessF() + darkAmount;
     v = v > 0.0 ? (v < 1.0 ? v : 1.0) : 0.0;
-    c.setHsvF(c.hslHueF(), c.hslSaturationF(), v);
+    c.setHsvF(c.hslHueF(), c.hslSaturationF(), (float)v);
     return c;
 }
 
diff --git a/desktop-widgets/qtwaitingspinner.cpp b/desktop-widgets/qtwaitingspinner.cpp
index 14e8669b0..bfe024b92 100644
--- a/desktop-widgets/qtwaitingspinner.cpp
+++ b/desktop-widgets/qtwaitingspinner.cpp
@@ -272,7 +272,7 @@ QColor QtWaitingSpinner::currentLineColor(int countDistance, int totalNrOfLines,
   int distanceThreshold =
 	  static_cast<int>(ceil((totalNrOfLines - 1) * trailFadePerc / 100.0));
   if (countDistance > distanceThreshold) {
-	color.setAlphaF(minAlphaF);
+	color.setAlphaF((float)minAlphaF);
   } else {
 	qreal alphaDiff = color.alphaF() - minAlphaF;
 	qreal gradient = alphaDiff / static_cast<qreal>(distanceThreshold + 1);
@@ -280,7 +280,7 @@ QColor QtWaitingSpinner::currentLineColor(int countDistance, int totalNrOfLines,
 
 	// If alpha is out of bounds, clip it.
 	resultAlpha = std::min(1.0, std::max(0.0, resultAlpha));
-	color.setAlphaF(resultAlpha);
+	color.setAlphaF((float)resultAlpha);
   }
   return color;
 }
diff --git a/profile-widget/divepercentageitem.cpp b/profile-widget/divepercentageitem.cpp
index 1e879406a..5b2d83474 100644
--- a/profile-widget/divepercentageitem.cpp
+++ b/profile-widget/divepercentageitem.cpp
@@ -52,27 +52,35 @@ static std::array<int, num_tissues> calcLinesPerTissue(int size)
 	return res;
 }
 
+static inline QRgb hsv2rgb(double h, double s, double v)
+{
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)  // they are just trolling us with these changes
+	QColor c = QColor::fromHslF((float)h, (float)s, (float)v);
+#else
+	QColor c = QColor::fromHslF(h, s, v);
+#endif
+	return c.rgba();
+}
+
 static QRgb colorScale(double value, int inert)
 {
-	QColor color;
 	double scaledValue = value / (AMB_PERCENTAGE * inert) * 1000.0;
 	if (scaledValue < 0.8)	// grade from cyan to blue to purple
-		color.setHsvF(0.5 + 0.25 * scaledValue / 0.8, 1.0, 1.0);
+		return hsv2rgb(0.5 + 0.25 * scaledValue / 0.8, 1.0, 1.0);
 	else if (scaledValue < 1.0)	// grade from magenta to black
-		color.setHsvF(0.75, 1.0, (1.0 - scaledValue) / 0.2);
+		return hsv2rgb(0.75, 1.0, (1.0 - scaledValue) / 0.2);
 	else if (value < AMB_PERCENTAGE)	// grade from black to bright green
-		color.setHsvF(0.333, 1.0, (value - AMB_PERCENTAGE * inert / 1000.0) / (AMB_PERCENTAGE - AMB_PERCENTAGE * inert / 1000.0));
+		return hsv2rgb(0.333, 1.0, (value - AMB_PERCENTAGE * inert / 1000.0) / (AMB_PERCENTAGE - AMB_PERCENTAGE * inert / 1000.0));
 	else if (value < 65)		// grade from bright green (0% M) to yellow-green (30% M)
-		color.setHsvF(0.333 - 0.133 * (value - AMB_PERCENTAGE) / (65.0 - AMB_PERCENTAGE), 1.0, 1.0);
+		return hsv2rgb(0.333 - 0.133 * (value - AMB_PERCENTAGE) / (65.0 - AMB_PERCENTAGE), 1.0, 1.0);
 	else if (value < 85)		// grade from yellow-green (30% M) to orange (70% M)
-		color.setHsvF(0.2 - 0.1 * (value - 65.0) / 20.0, 1.0, 1.0);
+		return hsv2rgb(0.2 - 0.1 * (value - 65.0) / 20.0, 1.0, 1.0);
 	else if (value < 100)		// grade from orange (70% M) to red (100% M)
-		color.setHsvF(0.1 * (100.0 - value) / 15.0, 1.0, 1.0);
+		return hsv2rgb(0.1 * (100.0 - value) / 15.0, 1.0, 1.0);
 	else if (value < 120)		// M value exceeded - grade from red to white
-		color.setHsvF(0.0, 1 - (value - 100.0) / 20.0, 1.0);
+		return hsv2rgb(0.0, 1 - (value - 100.0) / 20.0, 1.0);
 	else	// white
-		color.setHsvF(0.0, 0.0, 1.0);
-	return color.rgba();
+		return hsv2rgb(0.0, 0.0, 1.0);
 }
 
 void DivePercentageItem::replot(const dive *d, const struct divecomputer *dc, const plot_info &pi)
diff --git a/profile-widget/divepixmapcache.cpp b/profile-widget/divepixmapcache.cpp
index 4f487a41b..37c6146ae 100644
--- a/profile-widget/divepixmapcache.cpp
+++ b/profile-widget/divepixmapcache.cpp
@@ -2,6 +2,7 @@
 #include "divepixmapcache.h"
 #include "core/metrics.h"
 #include "core/qthelper.h" // for renderSVGIconWidth
+#include "core/color.h"
 
 #include <cmath>
 
@@ -49,7 +50,7 @@ DivePixmaps::DivePixmaps(int dpr) : dpr(dpr)
 	// The transparen pixmap is a very obscure feature to enable tooltips without showing a pixmap.
 	// See code in diveeventitem.cpp. This should probably be replaced by a different mechanism.
 	QPixmap transparentPixmap(lrint(4 * dprf), lrint(20 * dprf));
-	transparentPixmap.fill(QColor::fromRgbF(1.0, 1.0, 1.0, 0.01));
+	transparentPixmap.fill(makeColor(1.0, 1.0, 1.0, 0.01));
 }
 
 static std::vector<std::shared_ptr<const DivePixmaps>> cache;
diff --git a/stats/regressionitem.cpp b/stats/regressionitem.cpp
index 9f176c6ae..3377ec419 100644
--- a/stats/regressionitem.cpp
+++ b/stats/regressionitem.cpp
@@ -87,7 +87,7 @@ void RegressionItem::updatePosition()
 	img->fill(Qt::transparent);
 	if (confidence) {
 		QColor col(regressionItemColor);
-		col.setAlphaF(reg.r2);
+		col.setAlphaF((float)reg.r2);
 		painter->setPen(Qt::NoPen);
 		painter->setBrush(QBrush(col));
 		painter->drawPolygon(poly);