diff --git a/sw/inc/iodetect.hxx b/sw/inc/iodetect.hxx
index cce9b3225095..e49c8031589f 100644
--- a/sw/inc/iodetect.hxx
+++ b/sw/inc/iodetect.hxx
@@ -96,7 +96,7 @@ public:
     static bool IsValidStgFilter( const css::uno::Reference < css::embed::XStorage >& rStg, const SfxFilter& rFilter);
 
     static bool IsDetectableText( const sal_Char* pBuf, sal_uLong &rLen,
-            rtl_TextEncoding *pCharSet, bool *pSwap, LineEnd *pLineEnd=nullptr, bool bEncodedFilter = false );
+            rtl_TextEncoding *pCharSet, bool *pSwap, LineEnd *pLineEnd=nullptr );
 
     static const OUString GetSubStorageName( const SfxFilter& rFltr );
 };
diff --git a/sw/source/filter/basflt/iodetect.cxx b/sw/source/filter/basflt/iodetect.cxx
index 4fc0635b3985..1ab3626fe2a1 100644
--- a/sw/source/filter/basflt/iodetect.cxx
+++ b/sw/source/filter/basflt/iodetect.cxx
@@ -234,7 +234,7 @@ std::shared_ptr<const SfxFilter> SwIoSystem::GetFileFilter(const OUString& rFile
 }
 
 bool SwIoSystem::IsDetectableText(const sal_Char* pBuf, sal_uLong &rLen,
-    rtl_TextEncoding *pCharSet, bool *pSwap, LineEnd *pLineEnd, bool bEncodedFilter)
+    rtl_TextEncoding *pCharSet, bool *pSwap, LineEnd *pLineEnd)
 {
     bool bSwap = false;
     rtl_TextEncoding eCharSet = RTL_TEXTENCODING_DONTKNOW;
@@ -369,7 +369,7 @@ bool SwIoSystem::IsDetectableText(const sal_Char* pBuf, sal_uLong &rLen,
     if (pLineEnd)
         *pLineEnd = eLineEnd;
 
-    return bEncodedFilter || (!bIsBareUnicode && eSysLE == eLineEnd);
+    return !bIsBareUnicode && eSysLE == eLineEnd;
 }
 
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