diff --git a/mozilla/editor/libeditor/html/nsHTMLDataTransfer.cpp b/mozilla/editor/libeditor/html/nsHTMLDataTransfer.cpp
index d9eabe31566..72a965593a8 100644
--- a/mozilla/editor/libeditor/html/nsHTMLDataTransfer.cpp
+++ b/mozilla/editor/libeditor/html/nsHTMLDataTransfer.cpp
@@ -883,7 +883,7 @@ nsHTMLEditor::ParseCFHTML(nsCString & aCfhtml, PRUnichar **aStuffToPaste, PRUnic
// translate platform linebreaks for context
newStr = 0;
- oldLengthInChars = cntxtUcs2Str.Length() + 1; // +1 to include null terminator
+ oldLengthInChars = cntxtUcs2Str.Length(); // +1 to include null terminator
newLengthInChars = 0;
*aCfcontext = nsLinebreakConverter::ConvertUnicharLineBreaks(cntxtUcs2Str.get(),
nsLinebreakConverter::eLinebreakAny,