fix loss of an attribute in sqrt

Reviewed-on: https://git.onlyoffice.com/ONLYOFFICE/core/pulls/537

MsBinaryFile/XlsFile/Converter/xlsx_drawing_context.cpp

@@ -2554,6 +2554,13 @@ void xlsx_drawing_context::serialize_bitmap_fill(std::wostream & stream, _drawin
 						CP_XML_ATTR(L"thresh", *fill.biLevel * 1000);
 					}
 				}
+				if (fill.color.opacity > 0.00001)
+				{
+					CP_XML_NODE(L"a:alphaModFix")
+					{
+						CP_XML_ATTR(L"amt", (int)(fill.color.opacity * 100000));
+					}
+				}
 			}
 
 			CP_XML_NODE(L"a:srcRect")

OdfFile/Reader/Converter/StarMath2OOXML/cstarmathpars.cpp

@@ -94,6 +94,8 @@ namespace StarMath
 
 			if(pReader->GetAttribute() != nullptr && !CheckForLeftArgument(pReader->GetGlobalType()))
 				pElement->SetBaseAttribute(pReader->GetAttribute());
+			else if(pReader->GetAttribute() != nullptr && pElement->GetBaseType() == TypeElement::Index && dynamic_cast<CElementIndex*>(pElement)->GetType() == TypeElement::sqrt)
+				pElement->SetBaseAttribute(pReader->GetAttribute());
 			else if(pReader->GetAttribute() != nullptr && (pReader->GetLocalType() == TypeElement::plus || TypeElement::minus == pReader->GetLocalType() || TypeElement::frac == pReader->GetLocalType() || TypeElement::neg == pReader->GetLocalType()))
 				pElement->SetBaseAttribute(pReader->GetAttribute());
 			pReader->ClearReader();
@@ -2610,6 +2612,8 @@ namespace StarMath
 			m_pLeftArg->SetBaseAttribute(pAttribute);
 			this->SetBaseAttribute(m_pLeftArg->GetAttribute());
 		}
+		if(m_enTypeIndex == TypeElement::sqrt)
+			this->SetBaseAttribute(pAttribute);
 		if(m_pValueIndex != nullptr)
 			m_pValueIndex->SetAttribute(pAttribute);
 		if(m_pLeftArg != nullptr)