I'm not sure what happened to my last reply, but it appears to have not gone through.
I'm using a separate asset catalog for each target, and the messages icon's image set name was set in the messages extension's info.plist, as well as in the messages extension target's build settings Primary App Icon Set Name.
Syricr
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I'm using a separate asset catalog for each target, and the messages icon's image set name was set in the messages extension's info.plist, as well as in the messages extension target's build settings Primary App Icon Set Name.