[multimedia/kdenlive/release/26.08] src: Fix crash on ripple edit with project monitor hidden

Git commit 80c9d243ea065d2bb550d79cf21463bbdf51f326 by Jean-Baptiste Mardelle.
Committed on 18/08/2026 at 16:42.
Pushed by mardelle into branch 'release/26.08'.

Fix crash on ripple edit with project monitor hidden
Replaces !955

M  +3    -1    src/monitor/monitor.cpp
M  +4    -4    src/timeline2/model/trackmodel.cpp
M  +5    -1    src/timeline2/view/timelinecontroller.cpp
M  +1    -0    src/timeline2/view/timelinecontroller.h

https://invent.kde.org/multimedia/kdenlive/-/commit/80c9d243ea065d2bb550d79cf21463bbdf51f326

diff --git a/src/monitor/monitor.cpp b/src/monitor/monitor.cpp
index b0ff4cca24..9b7d77206f 100644
--- a/src/monitor/monitor.cpp
+++ b/src/monitor/monitor.cpp
@@ -1866,6 +1866,8 @@ void Monitor::slotRefreshMonitor(bool visible)
         if (slotActivateMonitor()) {
             start();
         }
+    } else {
+        stop();
     }
 }
 
@@ -3133,7 +3135,7 @@ void Monitor::setProducer(const QUuid uuid, std::shared_ptr<Mlt::Producer> produ
         m_dirty = false;
         m_displayedUuid = uuid;
     }
-    m_glMonitor->setProducer(std::move(producer), isActive(), pos);
+    m_glMonitor->setProducer(std::move(producer), isActive() && isVisible(), pos);
 }
 
 void Monitor::reconfigure()
diff --git a/src/timeline2/model/trackmodel.cpp b/src/timeline2/model/trackmodel.cpp
index 36b61163d1..d01d643d13 100644
--- a/src/timeline2/model/trackmodel.cpp
+++ b/src/timeline2/model/trackmodel.cpp
@@ -438,10 +438,10 @@ Fun TrackModel::requestClipDeletion_lambda(int clipId, bool updateView, bool fin
             ptr->_endRemoveRows();
         }
         int target_clip = clip_loc.second;
-        // lock MLT playlist so that we don't end up with invalid frames in monitor
-        m_playlists[target_track].lock();
         std::unique_ptr<Mlt::Field> field(m_track->field());
         field->block();
+        // lock MLT playlist so that we don't end up with invalid frames in monitor
+        m_playlists[target_track].lock();
         Q_ASSERT(target_clip < m_playlists[target_track].count());
         Q_ASSERT(!m_playlists[target_track].is_blank(target_clip));
         auto prod = m_playlists[target_track].replace_with_blank(target_clip);
@@ -451,8 +451,8 @@ Fun TrackModel::requestClipDeletion_lambda(int clipId, bool updateView, bool fin
             // m_allClips[clipId]->setSubPlaylistIndex(-1);
             m_allClips.erase(clipId);
             delete prod;
-            field->unblock();
             m_playlists[target_track].unlock();
+            field->unblock();
             if (auto ptr = m_parent.lock()) {
                 ptr->m_snaps->removePoint(old_in);
                 ptr->m_snaps->removePoint(old_out);
@@ -474,8 +474,8 @@ Fun TrackModel::requestClipDeletion_lambda(int clipId, bool updateView, bool fin
             }
             return true;
         }
-        field->unblock();
         m_playlists[target_track].unlock();
+        field->unblock();
         return false;
     };
 }
diff --git a/src/timeline2/view/timelinecontroller.cpp b/src/timeline2/view/timelinecontroller.cpp
index ec70542bcd..0e5f279e73 100644
--- a/src/timeline2/view/timelinecontroller.cpp
+++ b/src/timeline2/view/timelinecontroller.cpp
@@ -2583,9 +2583,13 @@ int TimelineController::requestItemRippleResize(int itemId, int size, bool right
 void TimelineController::updateTrimmingMode()
 {
     if (trimmingActive()) {
-        requestStartTrimmingMode();
+        if (m_trimmingClip != getMainSelectedClip()) {
+            requestStartTrimmingMode();
+            m_trimmingClip = getMainSelectedClip();
+        }
     } else {
         requestEndTrimmingMode();
+        m_trimmingClip = -1;
     }
 }
 
diff --git a/src/timeline2/view/timelinecontroller.h b/src/timeline2/view/timelinecontroller.h
index da250d9c4d..a8ecc46268 100644
--- a/src/timeline2/view/timelinecontroller.h
+++ b/src/timeline2/view/timelinecontroller.h
@@ -831,6 +831,7 @@ private:
     int m_videoTarget;
     int m_audioRef{-1};
     int m_timecodeRef{-1};
+    int m_trimmingClip{-1};
     int m_timelineMouseOffset{0};
     int m_hasAudioTarget {0};
     bool m_hasVideoTarget {false};