Added some obvious errors explanations

1 files changed, 2 insertions, 2 deletions

diff --git a/editor/editor_resource_preview.cpp b/editor/editor_resource_preview.cpp
index 5c15ebb1eb..b528cda8ff 100644
--- a/editor/editor_resource_preview.cpp
+++ b/editor/editor_resource_preview.cpp
@@ -203,7 +203,7 @@ void EditorResourcePreview::_generate_preview(Ref<ImageTexture> &r_texture, Ref<
 			}
 			Error err;
 			FileAccess *f = FileAccess::open(cache_base + ".txt", FileAccess::WRITE, &err);
-			ERR_FAIL_COND(err != OK);
+			ERR_FAIL_COND_MSG(err != OK, "Cannot create file '" + cache_base + ".txt'.");
 			f->store_line(itos(thumbnail_size));
 			f->store_line(itos(has_small_texture));
 			f->store_line(itos(FileAccess::get_modified_time(p_item.path)));
@@ -450,7 +450,7 @@ void EditorResourcePreview::check_for_invalidation(const String &p_path) {
 }
 
 void EditorResourcePreview::start() {
-	ERR_FAIL_COND(thread);
+	ERR_FAIL_COND_MSG(thread, "Thread already started.");
 	thread = Thread::create(_thread_func, this);
 }