diff --git a/core/src/processing/core/PApplet.java b/core/src/processing/core/PApplet.java
index 24c0d5d39a..9f3486a10d 100644
--- a/core/src/processing/core/PApplet.java
+++ b/core/src/processing/core/PApplet.java
@@ -2635,8 +2635,11 @@ protected void handleKeyEvent(KeyEvent event) {
         keyPressed = true;
         keyPressed(keyEvent);
       }
-      case KeyEvent.RELEASE -> {
-        pressedKeys.remove(((long) keyCode << Character.SIZE) | key);
+      case KeyEvent.RELEASE -> {    
+        pressedKeys.removeIf(hash -> {
+          int pressedKeyCode = (int)(hash >> Character.SIZE);
+          return pressedKeyCode == keyCode;
+        });
         keyPressed = !pressedKeys.isEmpty();
         keyReleased(keyEvent);
       }
@@ -2842,6 +2845,7 @@ public void focusGained() { }
   public void focusLost() {
     // TODO: if user overrides this without calling super it's not gonna work
     pressedKeys.clear();
+    keyPressed = false;
   }
 
 
diff --git a/core/test/processing/core/PAppletKeyEventTest.java b/core/test/processing/core/PAppletKeyEventTest.java
new file mode 100644
index 0000000000..19770ebc3d
--- /dev/null
+++ b/core/test/processing/core/PAppletKeyEventTest.java
@@ -0,0 +1,140 @@
+package processing.core;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import processing.event.KeyEvent;
+
+public class PAppletKeyEventTest {
+
+    private static final int SHIFT_MASK = 1;
+    private static final int CTRL_MASK = 2;
+    private static final int ALT_MASK = 4;
+
+    private PApplet applet;
+
+    @Before
+    public void setup() {
+        applet = new PApplet();
+    }
+
+    @Test
+    public void testSingleKeyPressAndRelease() {
+        KeyEvent pressEvent = new KeyEvent(null, 0L, KeyEvent.PRESS, 0, 'a', 65, false);
+        applet.handleKeyEvent(pressEvent);
+        Assert.assertEquals(1, applet.pressedKeys.size());
+
+        KeyEvent releaseEvent = new KeyEvent(null, 0L, KeyEvent.RELEASE, 0, 'a', 65, false);
+        applet.handleKeyEvent(releaseEvent);
+        Assert.assertEquals(0, applet.pressedKeys.size());
+        Assert.assertFalse(applet.keyPressed);
+    }
+
+    @Test
+    public void testShiftAndLetterSequence() {
+        KeyEvent pressA = new KeyEvent(null, 0L, KeyEvent.PRESS, 0, 'a', 65, false);
+        applet.handleKeyEvent(pressA);
+
+        KeyEvent pressShift = new KeyEvent(null, 0L, KeyEvent.PRESS, SHIFT_MASK, 'A', 16, false);
+        applet.handleKeyEvent(pressShift);
+
+        KeyEvent releaseA = new KeyEvent(null, 0L, KeyEvent.RELEASE, SHIFT_MASK, 'A', 65, false);
+        applet.handleKeyEvent(releaseA);
+
+        KeyEvent releaseShift = new KeyEvent(null, 0L, KeyEvent.RELEASE, 0, 'A', 16, false);
+        applet.handleKeyEvent(releaseShift);
+
+        Assert.assertFalse("keyPressed should be false after all keys released", applet.keyPressed);
+        Assert.assertTrue("pressedKeys should be empty", applet.pressedKeys.isEmpty());
+    }
+
+    @Test
+    public void testControlAndLetterSequence() {
+        KeyEvent pressCtrl = new KeyEvent(null, 0L, KeyEvent.PRESS, CTRL_MASK, '\0', 17, false);
+        applet.handleKeyEvent(pressCtrl);
+
+        KeyEvent pressC = new KeyEvent(null, 0L, KeyEvent.PRESS, CTRL_MASK, (char)3, 67, false);
+        applet.handleKeyEvent(pressC);
+
+        KeyEvent releaseC = new KeyEvent(null, 0L, KeyEvent.RELEASE, CTRL_MASK, 'c', 67, false);
+        applet.handleKeyEvent(releaseC);
+
+        KeyEvent releaseCtrl = new KeyEvent(null, 0L, KeyEvent.RELEASE, 0, '\0', 17, false);
+        applet.handleKeyEvent(releaseCtrl);
+
+        Assert.assertFalse("keyPressed should be false after all keys released", applet.keyPressed);
+        Assert.assertTrue("pressedKeys should be empty", applet.pressedKeys.isEmpty());
+    }
+
+    @Test
+    public void testAltAndLetterSequence() {
+        KeyEvent pressV = new KeyEvent(null, 0L, KeyEvent.PRESS, 0, 'v', 86, false);
+        applet.handleKeyEvent(pressV);
+
+        KeyEvent pressAlt = new KeyEvent(null, 0L, KeyEvent.PRESS, ALT_MASK, 'v', 18, false);
+        applet.handleKeyEvent(pressAlt);
+
+        KeyEvent releaseV = new KeyEvent(null, 0L, KeyEvent.RELEASE, ALT_MASK, 'v', 86, false);
+        applet.handleKeyEvent(releaseV);
+
+        KeyEvent releaseAlt = new KeyEvent(null, 0L, KeyEvent.RELEASE, 0, 'v', 18, false);
+        applet.handleKeyEvent(releaseAlt);
+
+        Assert.assertFalse("keyPressed should be false after all keys released", applet.keyPressed);
+        Assert.assertTrue("pressedKeys should be empty", applet.pressedKeys.isEmpty());
+    }
+
+    @Test
+    public void testKeyRepeat() {
+        applet.keyRepeatEnabled = false;
+
+        KeyEvent pressR = new KeyEvent(null, 0L, KeyEvent.PRESS, 0, 'r', 82, false);
+        applet.handleKeyEvent(pressR);
+
+        KeyEvent repeatR = new KeyEvent(null, 0L, KeyEvent.PRESS, 0, 'r', 82, true);
+        applet.handleKeyEvent(repeatR);
+
+        Assert.assertTrue("keyPressed should be true after key press", applet.keyPressed);
+        Assert.assertEquals("pressedKeys should have 1 entry", 1, applet.pressedKeys.size());
+
+        KeyEvent releaseR = new KeyEvent(null, 0L, KeyEvent.RELEASE, 0, 'r', 82, false);
+        applet.handleKeyEvent(releaseR);
+
+        Assert.assertFalse("keyPressed should be false after key release", applet.keyPressed);
+        Assert.assertEquals("pressedKeys should be empty", true, applet.pressedKeys.isEmpty());
+    }
+
+    @Test
+    public void testKeyRepeatEnabled() {
+        applet.keyRepeatEnabled = true;
+
+        KeyEvent pressT = new KeyEvent(null, 0L, KeyEvent.PRESS, 0, 't', 84, false);
+        applet.handleKeyEvent(pressT);
+
+        KeyEvent repeatT = new KeyEvent(null, 0L, KeyEvent.PRESS, 0, 't', 84, true);
+        applet.handleKeyEvent(repeatT);
+
+        Assert.assertTrue("keyPressed should be true with key repeat enabled", applet.keyPressed);
+        Assert.assertEquals("pressedKeys should have 1 entry", 1, applet.pressedKeys.size());
+
+        KeyEvent releaseT = new KeyEvent(null, 0L, KeyEvent.RELEASE, 0, 't', 84, false);
+        applet.handleKeyEvent(releaseT);
+
+        Assert.assertFalse("keyPressed should be false after key release", applet.keyPressed);
+        Assert.assertEquals("pressedKeys should be empty", true, applet.pressedKeys.isEmpty());
+    }
+
+    @Test
+    public void testKeyFocusLost() {
+        KeyEvent pressF = new KeyEvent(null, 0L, KeyEvent.PRESS, 0, 'f', 70, false);
+        applet.handleKeyEvent(pressF);
+
+        Assert.assertTrue("keyPressed should be true after key press", applet.keyPressed);
+        Assert.assertEquals("pressedKeys should have 1 entry", 1, applet.pressedKeys.size());
+
+        applet.focusLost();
+
+        Assert.assertFalse("keyPressed should be false after focus lost", applet.keyPressed);
+        Assert.assertEquals("pressedKeys should be empty after focus lost", true, applet.pressedKeys.isEmpty());
+    }
+}