From 91eb4ecb4c9c0ebfbc301837292398d224a8916c Mon Sep 17 00:00:00 2001
From: flurick <the3drick@gmail.com>
Date: Nov 02 2022 12:02:42 +0000
Subject: Keep selection valid when cutting frames 


Fixes #4392
---

diff --git a/toonz/sources/toonz/filmstripselection.cpp b/toonz/sources/toonz/filmstripselection.cpp
index 1771c28..0cf7978 100644
--- a/toonz/sources/toonz/filmstripselection.cpp
+++ b/toonz/sources/toonz/filmstripselection.cpp
@@ -237,7 +237,10 @@ void TFilmstripSelection::cutFrames() {
   TXshSimpleLevel *sl = TApp::instance()->getCurrentLevel()->getSimpleLevel();
   if (sl) {
     int firstSelectedIndex = sl->fid2index(*m_selectedFrames.begin());
-    assert(firstSelectedIndex >= 0);
+    if(firstSelectedIndex < 0 || firstSelectedIndex > sl->getFrameCount()) {
+      selectNone();
+      return;
+    }
     FilmstripCmd::cut(sl, m_selectedFrames);
     selectNone();
     TFrameId fId = (firstSelectedIndex == 0)