diff --git a/mk/check.mk b/mk/check.mk
index ef44f6d86c2..43829a4c951 100644
--- a/mk/check.mk
+++ b/mk/check.mk
@@ -42,11 +42,11 @@ check-test:
@$(call E, " $(DEPS_CHECK_TARGETS_ALL)")
.PHONY: check
-check: $(DEPS_CHECK_TARGETS_FAST) check-servo tidy
+check: $(DEPS_CHECK_TARGETS_FAST) check-servo check-content tidy
@$(call E, check: all)
.PHONY: check-all
-check-all: $(DEPS_CHECK_TARGETS_ALL) check-servo tidy
+check-all: $(DEPS_CHECK_TARGETS_ALL) check-servo check-content tidy
@$(call E, check: all)
.PHONY: check-servo
diff --git a/src/test/html/content/test_prototypes.js b/src/test/html/content/test_prototypes.js
index 327843439f5..f90170d856d 100644
--- a/src/test/html/content/test_prototypes.js
+++ b/src/test/html/content/test_prototypes.js
@@ -1,7 +1,7 @@
-is(HTMLImageElement instanceof HTMLElement, true);
-is(HTMLElement instanceof Element, true);
-is(Element instanceof Node, true);
-is(document instanceof Document, true);
-is(document.documentElement instanceof HTMLElement, true);
-is(document.documentElement instanceof Element, true);
+is(window.document.documentElement instanceof Node, true);
+is(window.document.documentElement instanceof Element, true);
+is(window.document.documentElement instanceof HTMLElement, true);
+is(window.document.documentElement instanceof HTMLHtmlElement, true);
+is(window.document instanceof Document, true);
+is(window.document instanceof HTMLDocument, true);
finish();
\ No newline at end of file
diff --git a/src/test/html/content/test_proxy_setter.html b/src/test/html/content/test_proxy_setter.html
new file mode 100644
index 00000000000..ed096bf5b3c
--- /dev/null
+++ b/src/test/html/content/test_proxy_setter.html
@@ -0,0 +1,9 @@
+
+
+
+
+
+
+
+
+
diff --git a/src/test/html/content/test_proxy_setter.js b/src/test/html/content/test_proxy_setter.js
new file mode 100644
index 00000000000..67f4585c15a
--- /dev/null
+++ b/src/test/html/content/test_proxy_setter.js
@@ -0,0 +1,4 @@
+is(window.document.title, '');
+window.document.title = 'foo';
+is(window.document.title, 'foo');
+finish();
\ No newline at end of file