Extension icon small in Illustrator only

I have an extension (CEP) for several Adobe products, including Illustrator and InDesign.  My `icons` definition in my `manifest.xml` is correct, in that it points to 23 x 23 pixel PNG files inside the extension, and in that same folder I have included `@2x.png` versions of those icons which are 46 x 46 pixels.

These icons display perfectly for me in all supported Adobe products.  However, I heard from a few Mac users that the icons all display correctly in every product except Illustrator.  In Illustrator, the icon appears as in my attached screenshot.

Given that the icon appears normally everywhere else, I suspect this is some bug in Illustrator.  Can this be investigated?  Or is it possible I need to fix something in my extension?  Thanks!