diff --git a/GUI/extenwindow.cpp b/GUI/extenwindow.cpp
index d4f07b1..9ab7c31 100644
--- a/GUI/extenwindow.cpp
+++ b/GUI/extenwindow.cpp
@@ -53,21 +53,14 @@ namespace
 
 bool DispatchSentenceToExtensions(std::wstring& sentence, const InfoForExtension* miscInfo)
 {
-	wchar_t* sentenceBuffer = (wchar_t*)HeapAlloc(GetProcessHeap(), 0, (sentence.size() + 1) * sizeof(wchar_t));
+	wchar_t* sentenceBuffer = (wchar_t*)HeapAlloc(GetProcessHeap(), HEAP_GENERATE_EXCEPTIONS, (sentence.size() + 1) * sizeof(wchar_t));
 	wcscpy_s(sentenceBuffer, sentence.size() + 1, sentence.c_str());
-
 	concurrency::reader_writer_lock::scoped_lock_read readLock(extenMutex);
 	for (const auto& extension : extensions)
-	{
-		wchar_t* nextBuffer = extension.callback(sentenceBuffer, miscInfo);
-		if (nextBuffer != sentenceBuffer) HeapFree(GetProcessHeap(), 0, sentenceBuffer);
-		if (nextBuffer == nullptr) return false;
-		sentenceBuffer = nextBuffer;
-	}
+		if (*(sentenceBuffer = extension.callback(sentenceBuffer, miscInfo)) == L'\0') break;
 	sentence = sentenceBuffer;
-
 	HeapFree(GetProcessHeap(), 0, sentenceBuffer);
-	return true;
+	return !sentence.empty();
 }
 
 ExtenWindow::ExtenWindow(QWidget* parent) :
diff --git a/extensions/extensionimpl.cpp b/extensions/extensionimpl.cpp
index ce3034a..e333bd4 100644
--- a/extensions/extensionimpl.cpp
+++ b/extensions/extensionimpl.cpp
@@ -5,12 +5,11 @@ bool ProcessSentence(std::wstring& sentence, SentenceInfo sentenceInfo);
 /**
 	* You shouldn't mess with this or even look at it unless you're certain you know what you're doing.
 	* Param sentence: pointer to sentence received by Textractor (UTF-16).
-	* You should not write beyond the end of this sentence. If you want Textractor to receive a larger sentence, copy it into your own buffer and return that.
-	* Please allocate the buffer using HeapAlloc() and not new[] or malloc() or something else: Textractor uses HeapFree() to free it.
-	* Param miscInfo: pointer to array containing misc info about the sentence. End of array is marked with name being nullptr.
-	* Return value: pointer to sentence Textractor takes for future processing and display. If nullptr, Textractor will destroy the sentence.
-	* Return 'sentence' unless you created a new sentence/buffer as mentioned above.
+	* This can be modified. Textractor uses the modified sentence for future processing and display. If empty (starts with null terminator), Textractor will destroy it.
 	* Textractor will display the sentence after all extensions have had a chance to process and/or modify it.
+	* The buffer is allocated using HeapAlloc(). If you want to make it larger, please use HeapReAlloc().
+	* Param miscInfo: pointer to array containing misc info about the sentence. End of array is marked with name being nullptr.
+	* Return value: the buffer used for the sentence. Remember to return a new pointer if HeapReAlloc() gave you one.
 	* THIS FUNCTION MAY BE RUN SEVERAL TIMES CONCURRENTLY: PLEASE ENSURE THAT IT IS THREAD SAFE!
 */
 extern "C" __declspec(dllexport) wchar_t* OnNewSentence(wchar_t* sentence, const InfoForExtension* miscInfo)
@@ -21,13 +20,13 @@ extern "C" __declspec(dllexport) wchar_t* OnNewSentence(wchar_t* sentence, const
 		int origLength = sentenceStr.size();
 		if (ProcessSentence(sentenceStr, SentenceInfo{ miscInfo }))
 		{
-			if (sentenceStr.empty()) return nullptr;
-			// No need to worry about freeing this: Textractor does it for you.
-			wchar_t* newSentence = sentenceStr.size() > origLength ? (wchar_t*)HeapAlloc(GetProcessHeap(), 0, (sentenceStr.size() + 1) * sizeof(wchar_t)) : sentence;
-			wcscpy_s(newSentence, sentenceStr.size() + 1, sentenceStr.c_str());
-			return newSentence;
+			if (sentenceStr.size() > origLength) sentence = (wchar_t*)HeapReAlloc(GetProcessHeap(), HEAP_GENERATE_EXCEPTIONS, sentence, (sentenceStr.size() + 1) * sizeof(wchar_t));
+			wcscpy_s(sentence, sentenceStr.size() + 1, sentenceStr.c_str());
 		}
-		else return sentence;
 	}
-	catch (SKIP) { return nullptr; }
+	catch (SKIP)
+	{
+		*sentence = L'\0';
+	}
+	return sentence;
 }