Fix bug #8889 by always issuing \protect in fragile environments.

(cherry picked from commit 3c1969574f)

src/mathed/InsetMathPhantom.cpp

@@ -120,6 +120,8 @@ void InsetMathPhantom::draw(PainterInfo & pi, int x, int y) const
 void InsetMathPhantom::write(WriteStream & os) const
 {
 	MathEnsurer ensurer(os);
+	if (os.fragile())
+		os << "\\protect";
 	switch (kind_) {
 	case phantom:
 		os << "\\phantom{";

src/mathed/MathMacro.cpp

@@ -704,8 +704,8 @@ void MathMacro::write(WriteStream & os) const
 	// normal mode
 	LASSERT(macro_, /**/);
 
-	// optional arguments make macros fragile
-	if (optionals_ > 0 && os.fragile())
+	// Always protect macros in a fragile environment
+	if (os.fragile())
 		os << "\\protect";
 	
 	os << "\\" << name();

status.20x

@@ -65,6 +65,8 @@ What's new
 
 - Fix bug where depth of pasted text was incorrectly set (bug 8891).
 
+- Fix clash between \protect and \ensuremath (bug 8889).
+
 
 * USER INTERFACE