lyx2lyx: fix convert_chunks for empty chunk layouts

Fixes: #9298

lib/lyx2lyx/lyx_2_1.py

@@ -4577,9 +4577,14 @@ def convert_chunks(document):
         # The last chunk should simply have an "@" in it
         # or at least end with "@" (can happen if @ is
         # preceded by a newline)
-        lastpar = ''.join(contents[-1])
+        lastpar = ''
+        if len(contents) > 0:
+            lastpar = ''.join(contents[-1])
         if not lastpar.endswith("@"):
             document.warning("Unexpected chunk content: chunk not terminated by '@'!")
+            if len(contents) == 0:
+                # convert empty chunk layouts to Standard
+                document.body[start] = "\\begin_layout Standard"
             continue
 
         if lastpar == "@":

status.21x

@@ -81,6 +81,8 @@ What's new
 
 - Fix import of LyX 2.0 IEEEtran documents (bug 9273).
 
+- Fix import of Chunk layout with trailing empty paragraph (bug 9298).
+
 
 * USER INTERFACE