looking into color FIXME's

@@ -1952,6 +1952,25 @@ static void BKE_nlastrip_validate_autoblends(NlaTrack *nlt, NlaStrip *nls)
   }
 }
 
+/* Ensure every transition's start/end properly set. */

@@ -1953,2 +1953,4 @@
 }
 
+/* Ensure every transition's start/end properly set. */
+static void nlastrip_validate_start_end(NlaStrip *strip)

@@ -1969,2 +1989,4 @@
+      nlastrip_validate_start_end(strip);
+
       /* auto-blending first */
       BKE_nlastrip_validate_autoblends(nlt, strip);

@@ -486,3 +486,3 @@
 
   /* draw 'inside' of strip itself */
-  if (non_solo == 0 && is_nlastrip_enabled(adt, nlt, strip)) {
+  if (non_solo == 0 && is_nlastrip_enabled(adt, nlt, strip) &&

@@ -58,0 +133,4 @@
+  const float offset_left = transdata_get_time_shuffle_offset_side(trans_datas, true);
+  const float offset_right = transdata_get_time_shuffle_offset_side(trans_datas, false);
+  BLI_assert(offset_left <= 0);
+  BLI_assert(offset_right >= 0);

@@ -84,0 +181,4 @@
+ * strips for overlap instead of all of them. */
+static void nlastrip_flag_overlaps(NlaStrip *strip)
+{
+  {

@@ -84,0 +198,4 @@
+/** Check the Transformation data for the given Strip, and fix any overlap. Then
+ * apply the Transformation.
+ */
+static void nlastrip_fix_overlapping(TransInfo *t, TransDataNla *tdn, NlaStrip *strip)

@@ -536,3 +757,2 @@
 
-    /* Perform after-transform validation. */
-    ED_nla_postop_refresh(&ac);
+  for (ale = anim_data.first; ale; ale = ale->next) {

@@ -835,0 +835,4 @@
+
+ /** When transforming strips, this flag is set when the strip is placed in an invalid location
+	* such as overlapping another strip or moved to a locked track. In such cases, the strip's
+	* location must be fixed. */

@@ -1969,0 +1988,4 @@
+
+      nlastrip_validate_transition_start_end(strip);
+
+      if (strip == NULL) {

@@ -1969,0 +1990,4 @@
+
+      if (strip == NULL) {
+        printf(
+            "NLA strip was in an invalid location and was removed by "

@@ -1969,0 +1992,4 @@
+        printf(
+            "NLA strip was in an invalid location and was removed by "
+            "nlastrip_validate_transition_start_end \n");
+        return;

@@ -84,0 +209,4 @@
+
+  PointerRNA strip_ptr;
+
+  for (short iter = 0; iter < 5; iter++) {

@@ -84,0 +210,4 @@
+  PointerRNA strip_ptr;
+
+  for (short iter = 0; iter < 5; iter++) {
+    const bool pExceeded = (prev != NULL) && (tdn->h1[0] < prev->end);

@@ -282,6 +475,8 @@ static void recalcData_nla(TransInfo *t)
 {
   SpaceNla *snla = (SpaceNla *)t->area->spacedata.first;
 
+  const bool is_translating = ELEM(t->mode, TFM_TRANSLATION);

@@ -502,0 +649,4 @@
+/** horizontally translate (shuffle) the transformed strip to a non-overlapping state. */
+static void nlastrip_shuffle_transformed(TransDataContainer *tc, TransDataNla *first_trans_data)
+{
+  /** Element: (IDGroupedTransData*) */

@@ -1969,0 +1988,4 @@
+
+      nlastrip_validate_transition_start_end(strip);
+
+      if (strip == NULL) {

@@ -1969,0 +1992,4 @@
+        printf(
+            "NLA strip was in an invalid location and was removed by "
+            "nlastrip_validate_transition_start_end \n");
+        return;

@@ -1955,0 +1955,4 @@
+/* Ensure every transition's start/end properly set.
+ * Strip will be removed / freed if it doesn't fit.
+ * Return value indicates if passed strip was freed or not. */
+static bool nlastrip_validate_transition_start_end(NlaStrip *strip)

@@ -1969,0 +1991,4 @@
+      if (nlastrip_validate_transition_start_end(strip)) {
+        printf(
+            "While moving NLA strips, a transition strip could no longer be applied to the new "
+            "positions and was removed. \n");

@@ -84,0 +202,4 @@
+  /* firstly, check if the proposed transform locations would overlap with any neighboring
+   * strips (barring transitions) which are absolute barriers since they are not being moved
+   *
+   * this is done as a iterative procedure (done 5 times max for now)

@@ -84,0 +214,4 @@
+    const bool p_exceeded = (prev != NULL) && (tdn->h1[0] < prev->end);
+    const bool n_exceeded = (next != NULL) && (tdn->h2[0] > next->start);
+
+    if ((p_exceeded && n_exceeded) || (iter == 4)) {