diff --git a/components/script/dom/webglbuffer.rs b/components/script/dom/webglbuffer.rs
index 66a3ce0af40..d874cc7a73a 100644
--- a/components/script/dom/webglbuffer.rs
+++ b/components/script/dom/webglbuffer.rs
@@ -154,6 +154,7 @@ impl WebGLBuffer {
 
 impl Drop for WebGLBuffer {
     fn drop(&mut self) {
-        self.delete();
+        self.mark_for_deletion();
+        assert!(self.is_deleted());
     }
 }
diff --git a/tests/wpt/webgl/meta/conformance/extensions/oes-texture-half-float.html.ini b/tests/wpt/webgl/meta/conformance/extensions/oes-texture-half-float.html.ini
index 7b42fd6ba4e..ae272da2b67 100644
--- a/tests/wpt/webgl/meta/conformance/extensions/oes-texture-half-float.html.ini
+++ b/tests/wpt/webgl/meta/conformance/extensions/oes-texture-half-float.html.ini
@@ -1,2 +1,4 @@
 [oes-texture-half-float.html]
-  expected: CRASH
+  [WebGL test #72: RGBA/HALF_FLOAT_OES is color renderable but EXT_color_buffer_half_float not exposed]
+    expected: FAIL
+
diff --git a/tests/wpt/webgl/meta/conformance/misc/expando-loss.html.ini b/tests/wpt/webgl/meta/conformance/misc/expando-loss.html.ini
deleted file mode 100644
index 2d422270afb..00000000000
--- a/tests/wpt/webgl/meta/conformance/misc/expando-loss.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[expando-loss.html]
-  expected: CRASH