Added layering order note 📝

recipe/0489-multimedia-canvas/index.md

@@ -32,6 +32,8 @@ When using timing for showing and hiding resources on a Canvas, a high degree of
 
 In this example, a still image, a video, and plaintext annotations are combined on a single Canvas to simulate a classroom assignment designed to introduce students to image study and notetaking in a compressed period of time. Note that this example contains material pedagogical design flaws and is not to be used as is for a classroom assignment.
 
+The simultaneously visible resources are listed in the Manifest from the foreground to the background. The timer video comes first in the Manifest, as the only currently capable viewer places resources on the Canvas so that the first resource is the most foregrounded.
+
 A person using a viewer that supports this recipe is presented first with the instruction to "Press Play", added using a time-bound plaintext annotation. After pressing play, additional instructions appear, also created using a time-bound plaintext annotation. When the time elapses on this annotation, the person is presented with a clock video overlaid on top of a still image. In the hypothetical assignment, a student would follow the instructions and take notes on the still image while the clock counts up the time allotted. After 30 seconds passes, the still image and clock video disappear, replaced by text instructions to close the browser. These final instructions stay visible for approximately 2-1/2 minutes to avoid an immediate return to the initial instructions.
 
 {% include manifest_links.html manifest="manifest.json" %}