diff --git a/extensions/spellcheck/hunspell/moz.build b/extensions/spellcheck/hunspell/moz.build
index 1c31aea6ff18..8dc89413ad07 100644
--- a/extensions/spellcheck/hunspell/moz.build
+++ b/extensions/spellcheck/hunspell/moz.build
@@ -4,7 +4,10 @@
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
-DIRS += ["glue", "src"]
+DIRS += ["glue"]
+
+if not CONFIG["MOZ_WASM_SANDBOXING_HUNSPELL"]:
+    DIRS += ["src"]
 
 if CONFIG["ENABLE_TESTS"]:
     XPCSHELL_TESTS_MANIFESTS += ["tests/unit/xpcshell.ini"]
diff --git a/modules/woff2/moz.build b/modules/woff2/moz.build
index 310f9117b4c7..3af9c00923c0 100644
--- a/modules/woff2/moz.build
+++ b/modules/woff2/moz.build
@@ -9,7 +9,8 @@ include("sources.mozbuild")
 with Files('**'):
     BUG_COMPONENT = ('Core', 'Graphics: Text')
 
-UNIFIED_SOURCES += woff2_sources
+if not CONFIG["MOZ_WASM_SANDBOXING_WOFF2"]:
+    UNIFIED_SOURCES += woff2_sources
 
 EXPORTS.woff2 += [
     'include/woff2/decode.h',