'Coalesce' fails to find fallback image with 'fill-pattern' and 'line-pattern'

[SnailBones]

mapbox-gl-js version: v2.5.0

browser: Chrome & Firefox

Steps to Trigger Behavior

Create a fallback image expression for a line or polygon. Example:

'fill-pattern': [
    "coalesce",
      ["image", ["get", "icon"]],
      ["image", "rocket-15"],
  ]

I think that this will occur with any expression that meets the following:

• for fill-pattern or line-pattern
• with coalesce
• and with at least one image wrapping a get

Link to Demonstration

Expected Behavior

The area with an invalid image name should display as the fallback rocket icon.

Actual Behavior

The area with an invalid image name doesn't render. The console displays:

"Image 'missing-icon' could not be loaded. Please make sure you have added the image with map.addImage() or a 'sprite' property in your style. You can provide missing images by listening for the 'styleimagemissing' map event."

Oddly, changing the second image expression to a string leads to ALL polygons displaying the fallback image:

'fill-pattern': [
    "coalesce",
      ["image", ["get", "icon"]],
      "rocket-15"
  ]

When a get statement is included, ALL 'image' expressions inside of the coalesce seem to evaluate to false.

@arindam1993 thoughts on why this might be happening?