Not sure where to file this, but I noticed this during testing (see attached screenshot). I am running (19A487l) of Catalina

Whenever I download a version of Firefox, I get a generic disk image icon that looks more like a page icon. I can right click and eject it like I normally would do after installation.

Probably a dupe of bug 1557218.

(In reply to Timothy Nikkel (:tnikkel) from comment #1)

Probably a dupe of bug 1557218.

Yes, this is a dupe.

This is a different bug. Bug 1557218 is about drawing of system icons inside Firefox windows. This bug is about displaying a Firefox-specific icon in Finder / on the Desktop.

Marcia, can you check whether "custom" DMG icons of any other apps still work? For example the Telegram and Whatsapp macOS app dmgs show custom icons on their mounted dmg images on at least my 10.12 machine.

(In reply to Markus Stange [:mstange] from comment #4)

Marcia, can you check whether "custom" DMG icons of any other apps still work? For example the Telegram and Whatsapp macOS app dmgs show custom icons on their mounted dmg images on at least my 10.12 machine.

From what I can see the same thing happens with the Telegram icon - it is not rendered either.

Thanks. In that case there's probably nothing we can do from our side, unless this was an intentional API change from Apple that they published in their documentation.

(In reply to Markus Stange [:mstange] from comment #3)

This is a different bug. Bug 1557218 is about drawing of system icons inside Firefox windows. This bug is about displaying a Firefox-specific icon in Finder / on the Desktop.

My mistake. Thanks for unduping.

Running the most recent beta from today ((19A501i), I am no longer seeing this issue. I downloaded Firefox Developer Edition and I now see the icon on the Desktop. Resolving this as WFM.