diff --git a/libs/image/kis_keyframe_channel.h b/libs/image/kis_keyframe_channel.h
--- a/libs/image/kis_keyframe_channel.h
+++ b/libs/image/kis_keyframe_channel.h
@@ -147,6 +147,7 @@
     virtual KisKeyframeSP loadKeyframe(const QDomElement &keyframeNode) = 0;
     virtual void saveKeyframe(KisKeyframeSP keyframe, QDomElement keyframeElement, const QString &layerFilename) = 0;
 
+    void workaroundBrokenFrameTimeBug(int *time);
 
 private:
     KisKeyframeSP replaceKeyframeAt(int time, KisKeyframeSP newKeyframe);
diff --git a/libs/image/kis_keyframe_channel.cpp b/libs/image/kis_keyframe_channel.cpp
--- a/libs/image/kis_keyframe_channel.cpp
+++ b/libs/image/kis_keyframe_channel.cpp
@@ -46,12 +46,14 @@
         node = newParentNode;
         id = rhs.id;
         defaultBounds = rhs.defaultBounds;
+        haveBrokenFrameTimeBug = rhs.haveBrokenFrameTimeBug;
     }
 
     KeyframesMap keys;
     KisNodeWSP node;
     KoID id;
     KisDefaultBoundsBaseSP defaultBounds;
+    bool haveBrokenFrameTimeBug = false;
 };
 
 KisKeyframeChannel::KisKeyframeChannel(const KoID &id, KisDefaultBoundsBaseSP defaultBounds)
@@ -516,6 +518,7 @@
         if (keyframeNode.nodeName().toUpper() != "KEYFRAME") continue;
 
         KisKeyframeSP keyframe = loadKeyframe(keyframeNode);
+        KIS_SAFE_ASSERT_RECOVER(keyframe) { continue; }
 
         if (keyframeNode.hasAttribute("color-label")) {
             keyframe->setColorLabel(keyframeNode.attribute("color-label").toUInt());
@@ -608,6 +611,33 @@
     }
 }
 
+void KisKeyframeChannel::workaroundBrokenFrameTimeBug(int *time)
+{
+    /**
+     * Between Krita 4.1 and 4.4 Krita had a bug which resulted in creating frames
+     * with negative time stamp. The bug has been fixed, but there might be some files
+     * still in the wild.
+     *
+     * TODO: remove this workaround in Krita 5.0, when no such file are left :)
+     */
+
+    if (*time < 0) {
+        qWarning() << "WARNING: Loading a file with negative animation frames!";
+        qWarning() << "         The file has been saved with a buggy version of Krita.";
+        qWarning() << "         All the frames with negative ids will be dropped!";
+        qWarning() << "         " << ppVar(this->id()) << ppVar(*time);
+
+        m_d->haveBrokenFrameTimeBug = true;
+        *time = 0;
+    }
+
+    if (m_d->haveBrokenFrameTimeBug) {
+        while (keyframeAt(*time)) {
+            (*time)++;
+        }
+    }
+}
+
 int KisKeyframeChannel::currentTime() const
 {
     return m_d->defaultBounds->currentTime();
diff --git a/libs/image/kis_raster_keyframe_channel.cpp b/libs/image/kis_raster_keyframe_channel.cpp
--- a/libs/image/kis_raster_keyframe_channel.cpp
+++ b/libs/image/kis_raster_keyframe_channel.cpp
@@ -260,7 +260,8 @@
 
 KisKeyframeSP KisRasterKeyframeChannel::loadKeyframe(const QDomElement &keyframeNode)
 {
-    int time = keyframeNode.attribute("time").toUInt();
+    int time = keyframeNode.attribute("time").toInt();
+    workaroundBrokenFrameTimeBug(&time);
 
     QPoint offset;
     KisDomUtils::loadValue(keyframeNode, "offset", &offset);
@@ -271,7 +272,7 @@
     if (m_d->frameFilenames.isEmpty()) {
         // First keyframe loaded: use the existing frame
 
-        Q_ASSERT(keyframeCount() == 1);
+        KIS_SAFE_ASSERT_RECOVER_NOOP(keyframeCount() == 1);
         keyframe = constKeys().begin().value();
 
         // Remove from keys. It will get reinserted with new time once we return
diff --git a/libs/image/kis_scalar_keyframe_channel.cpp b/libs/image/kis_scalar_keyframe_channel.cpp
--- a/libs/image/kis_scalar_keyframe_channel.cpp
+++ b/libs/image/kis_scalar_keyframe_channel.cpp
@@ -442,7 +442,9 @@
 
 KisKeyframeSP KisScalarKeyframeChannel::loadKeyframe(const QDomElement &keyframeNode)
 {
-    int time = keyframeNode.toElement().attribute("time").toUInt();
+    int time = keyframeNode.toElement().attribute("time").toInt();
+    workaroundBrokenFrameTimeBug(&time);
+
     qreal value = KisDomUtils::toDouble(keyframeNode.toElement().attribute("value"));
 
     KUndo2Command tempParentCommand;
diff --git a/plugins/tools/tool_transform2/kis_transform_args_keyframe_channel.cpp b/plugins/tools/tool_transform2/kis_transform_args_keyframe_channel.cpp
--- a/plugins/tools/tool_transform2/kis_transform_args_keyframe_channel.cpp
+++ b/plugins/tools/tool_transform2/kis_transform_args_keyframe_channel.cpp
@@ -106,7 +106,9 @@
     ToolTransformArgs args;
     args.fromXML(keyframeNode);
 
-    int time = keyframeNode.attribute("time").toUInt();
+    int time = keyframeNode.attribute("time").toInt();
+    workaroundBrokenFrameTimeBug(&time);
+
     KisTransformArgsKeyframe *keyframe = new KisTransformArgsKeyframe(this, time, args);
 
     return toQShared(keyframe);