5 files changed, 28 insertions, 28 deletions
diff --git a/source/blender/sequencer/intern/sequencer.c b/source/blender/sequencer/intern/sequencer.c
index 908a5bd4f79..e4120a3cf95 100644
--- a/source/blender/sequencer/intern/sequencer.c
+++ b/source/blender/sequencer/intern/sequencer.c
@@ -140,6 +140,7 @@ Sequence *SEQ_sequence_alloc(ListBase *lb, int timeline_frame, int machine, int
   seq->pitch = 1.0f;
   seq->scene_sound = NULL;
   seq->type = type;
+  seq->blend_mode = SEQ_TYPE_ALPHAOVER;
 
   seq->strip = seq_strip_alloc(type);
   seq->stereo3d_format = MEM_callocN(sizeof(Stereo3dFormat), "Sequence Stereo Format");
@@ -418,6 +419,10 @@ void SEQ_meta_stack_free(Editing *ed, MetaStack *ms)
 
 MetaStack *SEQ_meta_stack_active_get(const Editing *ed)
 {
+  if (ed == NULL) {
+    return NULL;
+  }
+
   return ed->metastack.last;
 }
 
diff --git a/source/blender/sequencer/intern/strip_add.c b/source/blender/sequencer/intern/strip_add.c
index a4b537b9074..f342765eec9 100644
--- a/source/blender/sequencer/intern/strip_add.c
+++ b/source/blender/sequencer/intern/strip_add.c
@@ -141,7 +141,6 @@ Sequence *SEQ_add_scene_strip(Scene *scene, ListBase *seqbase, struct SeqLoadDat
 {
   Sequence *seq = SEQ_sequence_alloc(
       seqbase, load_data->start_frame, load_data->channel, SEQ_TYPE_SCENE);
-  seq->blend_mode = SEQ_TYPE_ALPHAOVER;
   seq->scene = load_data->scene;
   seq->len = load_data->scene->r.efra - load_data->scene->r.sfra + 1;
   id_us_ensure_real((ID *)load_data->scene);
@@ -154,7 +153,6 @@ Sequence *SEQ_add_movieclip_strip(Scene *scene, ListBase *seqbase, struct SeqLoa
 {
   Sequence *seq = SEQ_sequence_alloc(
       seqbase, load_data->start_frame, load_data->channel, SEQ_TYPE_MOVIECLIP);
-  seq->blend_mode = SEQ_TYPE_ALPHAOVER;
   seq->clip = load_data->clip;
   seq->len = BKE_movieclip_get_duration(load_data->clip);
   id_us_ensure_real((ID *)load_data->clip);
@@ -167,7 +165,6 @@ Sequence *SEQ_add_mask_strip(Scene *scene, ListBase *seqbase, struct SeqLoadData
 {
   Sequence *seq = SEQ_sequence_alloc(
       seqbase, load_data->start_frame, load_data->channel, SEQ_TYPE_MASK);
-  seq->blend_mode = SEQ_TYPE_ALPHAOVER;
   seq->mask = load_data->mask;
   seq->len = BKE_mask_get_duration(load_data->mask);
   id_us_ensure_real((ID *)load_data->mask);
@@ -191,9 +188,6 @@ Sequence *SEQ_add_effect_strip(Scene *scene, ListBase *seqbase, struct SeqLoadDa
   if (SEQ_effect_get_num_inputs(seq->type) == 1) {
     seq->blend_mode = seq->seq1->blend_mode;
   }
-  else {
-    seq->blend_mode = SEQ_TYPE_ALPHAOVER;
-  }
 
   if (!load_data->effect.seq1) {
     seq->len = 1; /* Effect is generator, set non zero length. */
@@ -250,7 +244,6 @@ Sequence *SEQ_add_image_strip(Main *bmain, Scene *scene, ListBase *seqbase, SeqL
 {
   Sequence *seq = SEQ_sequence_alloc(
       seqbase, load_data->start_frame, load_data->channel, SEQ_TYPE_IMAGE);
-  seq->blend_mode = SEQ_TYPE_ALPHAOVER; /* so alpha adjustment fade to the strip below */
   seq->len = load_data->image.len;
   Strip *strip = seq->strip;
   strip->stripdata = MEM_callocN(load_data->image.len * sizeof(StripElem), "stripelem");
@@ -482,8 +475,6 @@ Sequence *SEQ_add_movie_strip(
     }
   }
 
-  seq->blend_mode = SEQ_TYPE_ALPHAOVER; /* so alpha adjustment fade to the strip below */
-
   if (anim_arr[0] != NULL) {
     seq->len = IMB_anim_get_duration(anim_arr[0], IMB_TC_RECORD_RUN);
 
diff --git a/source/blender/sequencer/intern/strip_edit.c b/source/blender/sequencer/intern/strip_edit.c
index 912ba9d41db..cf303e5be4e 100644
--- a/source/blender/sequencer/intern/strip_edit.c
+++ b/source/blender/sequencer/intern/strip_edit.c
@@ -489,21 +489,27 @@ Sequence *SEQ_edit_strip_split(Main *bmain,
   ListBase right_strips = {NULL, NULL};
   SEQ_sequence_base_dupli_recursive(scene, scene, &right_strips, &left_strips, SEQ_DUPE_ALL, 0);
 
-  /* Split strips. */
   Sequence *left_seq = left_strips.first;
   Sequence *right_seq = right_strips.first;
-  Sequence *return_seq = right_strips.first;
+  Sequence *return_seq = NULL;
 
-  /* Strips can't be tagged while in detached `seqbase`. Collect all strips which needs to be
-   * deleted and delay tagging until they are moved back to `seqbase` in `Editing`. */
-  SeqCollection *strips_to_delete = SEQ_collection_create(__func__);
+  /* Move strips from detached `ListBase`, otherwise they can't be flagged for removal,
+   * SEQ_time_update_sequence can fail to update meta strips and they can't be renamed.
+   * This is because these functions check all strips in `Editing` to manage relationships. */
+  BLI_movelisttolist(seqbase, &left_strips);
+  BLI_movelisttolist(seqbase, &right_strips);
 
+  /* Split strips. */
   while (left_seq && right_seq) {
     if (left_seq->startdisp >= timeline_frame) {
-      SEQ_collection_append_strip(left_seq, strips_to_delete);
+      SEQ_edit_flag_for_removal(scene, seqbase, left_seq);
     }
     if (right_seq->enddisp <= timeline_frame) {
-      SEQ_collection_append_strip(right_seq, strips_to_delete);
+      SEQ_edit_flag_for_removal(scene, seqbase, right_seq);
+    }
+    else if (return_seq == NULL) {
+      /* Store return value - pointer to strip that will not be removed. */
+      return_seq = right_seq;
     }
 
     seq_edit_split_handle_strip_offsets(
@@ -512,20 +518,14 @@ Sequence *SEQ_edit_strip_split(Main *bmain,
     right_seq = right_seq->next;
   }
 
-  seq = right_strips.first;
-  BLI_movelisttolist(seqbase, &left_strips);
-  BLI_movelisttolist(seqbase, &right_strips);
+  SEQ_edit_remove_flagged_sequences(scene, seqbase);
 
-  for (; seq; seq = seq->next) {
-    SEQ_ensure_unique_name(seq, scene);
+  /* Rename duplicated strips. */
+  Sequence *seq_rename = return_seq;
+  for (; seq_rename; seq_rename = seq_rename->next) {
+    SEQ_ensure_unique_name(seq_rename, scene);
   }
 
-  Sequence *seq_delete;
-  SEQ_ITERATOR_FOREACH (seq_delete, strips_to_delete) {
-    SEQ_edit_flag_for_removal(scene, seqbase, seq_delete);
-  }
-  SEQ_edit_remove_flagged_sequences(scene, seqbase);
-  SEQ_collection_free(strips_to_delete);
   return return_seq;
 }
 
diff --git a/source/blender/sequencer/intern/strip_time.c b/source/blender/sequencer/intern/strip_time.c
index 3228277ce72..31ee20cb6ca 100644
--- a/source/blender/sequencer/intern/strip_time.c
+++ b/source/blender/sequencer/intern/strip_time.c
@@ -193,6 +193,10 @@ static void seq_time_update_meta_strip(Scene *scene, Sequence *seq_meta)
 
 void SEQ_time_update_meta_strip_range(Scene *scene, Sequence *seq_meta)
 {
+  if (seq_meta == NULL) {
+    return;
+  }
+
   seq_time_update_meta_strip(scene, seq_meta);
 
   /* Prevent meta-strip to move in timeline. */
diff --git a/source/blender/sequencer/intern/utils.c b/source/blender/sequencer/intern/utils.c
index cd779b0b0c7..156c6ac4cb9 100644
--- a/source/blender/sequencer/intern/utils.c
+++ b/source/blender/sequencer/intern/utils.c
@@ -446,7 +446,7 @@ Sequence *SEQ_get_meta_by_seqbase(ListBase *seqbase_main, ListBase *meta_seqbase
 {
   SeqCollection *strips = SEQ_query_all_strips_recursive(seqbase_main);
 
-  Sequence *seq;
+  Sequence *seq = NULL;
   SEQ_ITERATOR_FOREACH (seq, strips) {
     if (seq->type == SEQ_TYPE_META && &seq->seqbase == meta_seqbase) {
       break;