diff --git a/src/graphics/PreviewLoader.cpp b/src/graphics/PreviewLoader.cpp
index 198d6d96ab..a350a4939b 100644
--- a/src/graphics/PreviewLoader.cpp
+++ b/src/graphics/PreviewLoader.cpp
@@ -809,6 +809,7 @@ void PreviewLoader::Impl::dumpPreamble(otexstream & os, Flavor flavor) const
 	runparams.moving_arg = true;
 	runparams.free_spacing = true;
 	runparams.is_child = buffer_.parent();
+	runparams.for_preview = true;
 	buffer_.writeLaTeXSource(os, buffer_.filePath(), runparams, Buffer::OnlyPreamble);
 
 	// FIXME! This is a HACK! The proper fix is to control the 'true'
diff --git a/src/insets/InsetBranch.cpp b/src/insets/InsetBranch.cpp
index 7a97e2c3b4..229e1bc37e 100644
--- a/src/insets/InsetBranch.cpp
+++ b/src/insets/InsetBranch.cpp
@@ -22,6 +22,7 @@
 #include "FuncRequest.h"
 #include "FuncStatus.h"
 #include "Inset.h"
+#include "LaTeXFeatures.h"
 #include "Lexer.h"
 #include "LyX.h"
 #include "output_docbook.h"
@@ -340,7 +341,8 @@ void InsetBranch::forOutliner(docstring & os, size_t const maxlen,
 
 void InsetBranch::validate(LaTeXFeatures & features) const
 {
-	if (producesOutput())
+	// Showing previews in a disabled branch may require stuff
+	if (producesOutput() || features.runparams().for_preview)
 		InsetCollapsible::validate(features);
 }
 
diff --git a/src/insets/InsetNote.cpp b/src/insets/InsetNote.cpp
index a7a0dc16ab..b12b755fba 100644
--- a/src/insets/InsetNote.cpp
+++ b/src/insets/InsetNote.cpp
@@ -334,6 +334,9 @@ void InsetNote::validate(LaTeXFeatures & features) const
 		InsetCollapsible::validate(features);
 		break;
 	case InsetNoteParams::Note:
+		// Showing previews in this inset may require stuff
+		if (features.runparams().for_preview)
+			InsetCollapsible::validate(features);
 		break;
 	}
 }