From 84d99a5902f84e7087d81b8bd24943b2a9a62086 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sybren=20A=2E=20St=C3=BCvel?= <sybren@blender.org>
Date: Mon, 13 Oct 2025 12:53:50 +0200
Subject: [PATCH] Fix: Timeline versioning conflict with pre-2.80 files

Move the versioning code that switches the Timeline editor to Dope
Sheet from the 'first' to the 'after linking' versioning stage.

There was already versioning code that effectively turns the Dope
Sheet back into a Timeline, for pre-2.80 files, and this runs in the
'after linking' stage. The 5.0 versioning code now correctly runs
after this.

Fixes: #147742

Pull Request: https://projects.blender.org/blender/blender/pulls/147734
---
 .../blenloader/intern/versioning_500.cc       | 62 ++++++++++---------
 1 file changed, 33 insertions(+), 29 deletions(-)

diff --git a/source/blender/blenloader/intern/versioning_500.cc b/source/blender/blenloader/intern/versioning_500.cc
index 8eb96a4ccd5..4aca1992862 100644
--- a/source/blender/blenloader/intern/versioning_500.cc
+++ b/source/blender/blenloader/intern/versioning_500.cc
@@ -2687,6 +2687,39 @@ void do_versions_after_linking_500(FileData *fd, Main *bmain)
     }
   }
 
+  if (!MAIN_VERSION_FILE_ATLEAST(bmain, 500, 100)) {
+    /* Note: this HAS to happen in the 'after linking' stage, because
+     * #do_version_area_change_space_to_space_action() basically performs the opposite operation
+     * and is called from #do_versions_after_linking_280(). */
+    LISTBASE_FOREACH (bScreen *, screen, &bmain->screens) {
+      LISTBASE_FOREACH (ScrArea *, area, &screen->areabase) {
+        LISTBASE_FOREACH (SpaceLink *, sl, &area->spacedata) {
+          if (!ELEM(sl->spacetype, SPACE_ACTION)) {
+            continue;
+          }
+          SpaceAction *saction = reinterpret_cast<SpaceAction *>(sl);
+          const eAnimEdit_Context dopesheet_mode = eAnimEdit_Context(saction->mode);
+          if (dopesheet_mode != SACTCONT_TIMELINE) {
+            continue;
+          }
+          /* Switching to dopesheet since that is the closest to the timeline view. */
+          saction->mode = SACTCONT_DOPESHEET;
+          /* The multiplication by 2 assumes that the time control footer has the same size as the
+           * header. The header is only shown if there is enough space for both. */
+          const bool show_header = area->winy > (HEADERY * UI_SCALE_FAC) * 2;
+          LISTBASE_FOREACH (ARegion *, region, &area->regionbase) {
+            if (!show_header && region->regiontype == RGN_TYPE_HEADER) {
+              region->flag |= RGN_FLAG_HIDDEN;
+            }
+            if (region->regiontype == RGN_TYPE_FOOTER) {
+              region->flag &= ~RGN_FLAG_HIDDEN;
+            }
+          }
+        }
+      }
+    }
+  }
+
   if (!MAIN_VERSION_FILE_ATLEAST(bmain, 500, 101)) {
     const uint8_t default_flags = DNA_struct_default_get(ToolSettings)->fix_to_cam_flag;
     LISTBASE_FOREACH (Scene *, scene, &bmain->scenes) {
@@ -3836,35 +3869,6 @@ void blo_do_versions_500(FileData *fd, Library * /*lib*/, Main *bmain)
     }
   }
 
-  if (!MAIN_VERSION_FILE_ATLEAST(bmain, 500, 100)) {
-    LISTBASE_FOREACH (bScreen *, screen, &bmain->screens) {
-      LISTBASE_FOREACH (ScrArea *, area, &screen->areabase) {
-        LISTBASE_FOREACH (SpaceLink *, sl, &area->spacedata) {
-          if (!ELEM(sl->spacetype, SPACE_ACTION)) {
-            continue;
-          }
-          SpaceAction *saction = reinterpret_cast<SpaceAction *>(sl);
-          if (saction->mode != SACTCONT_TIMELINE) {
-            continue;
-          }
-          /* Switching to dopesheet since that is the closest to the timeline view. */
-          saction->mode = SACTCONT_DOPESHEET;
-          /* The multiplication by 2 assumes that the time control footer has the same size as the
-           * header. The header is only shown if there is enough space for both. */
-          const bool show_header = area->winy > (HEADERY * UI_SCALE_FAC) * 2;
-          LISTBASE_FOREACH (ARegion *, region, &area->regionbase) {
-            if (!show_header && region->regiontype == RGN_TYPE_HEADER) {
-              region->flag |= RGN_FLAG_HIDDEN;
-            }
-            if (region->regiontype == RGN_TYPE_FOOTER) {
-              region->flag &= ~RGN_FLAG_HIDDEN;
-            }
-          }
-        }
-      }
-    }
-  }
-
   if (!MAIN_VERSION_FILE_ATLEAST(bmain, 500, 102)) {
     LISTBASE_FOREACH (Scene *, scene, &bmain->scenes) {
       scene->r.time_jump_delta = 1.0f;