Thanks for your support, your suggestion saved my day! Maybe the explanation could help some other devs: In the last crash report, I've found this line: "exception" : {"codes":"0x0000000000000001, 0x00000001a6c79c04","rawCodes":[1,7093066756],"type":"EXC_BREAKPOINT","signal":"SIGTRAP"} Searching into the forum helped me again: https://developer.apple.com/forums/thread/46559?answerId=322813022#322813022 Effectively, I added MyApp's icon in an unconventional manner... Dragging & dropping it from another project. So, as a quick experiment I commented these lines: override var toolbarItemImage: NSImage { get { return NSImage(named: NSImage.Name("AppIcon"))! } } And everything worked fine 👌 Thank you again! 😊

Thank you for your support. These are the results of my experiments: I configured the Product > Analyze action to build in Release, and the resulting app works as expected: the Extension is recognised and loaded, in a fully functional way. I followed the steps to Archive & Export the app, using several signing methods. Namely: a) (From the organizer) Distribute app > Custom > Direct Distribution > Export > Developement Team = HIVE DIGITAL LABS > Automatically manage signing. Then the summary shows: Team: HIVE DIGITAL LABS SRL Certificate: Developer ID Application (Expires 01/02/27) Profile: None b) Distribute app > Custom > Direct Distribution > Export > Development Team = HIVE DIGITAL LABS > Manually manage signing, then I use my team's Developer ID certificate, proper Eligible profiles, and the summary shows: Team: HIVE DIGITAL LABS SRL Certificate: Developer ID Application (Expires 01/02/27) Profile: Release Cut and Paste (Expires 24/03/43) c) Distribute app > Custom > Debugging > Development Team = HIVE DIGITAL LABS > Automatically manage signing. Then the summary shows: Team: HIVE DIGITAL LABS SRL Certificate: Apple Development (Expires 28/03/26) Profile: None d) Distribute app > Custom > Debugging> Development Team = HIVE DIGITAL LABS > Manually manage signing, then I use my Apple Development certificate, proper Eligible profiles, and the summary shows: Team: HIVE DIGITAL LABS SRL Certificate: Apple Development (Expires 28/03/26) Profile: Debug Cut and Paste (Expires 28/03/26) e) Distribute app > Custom > Copy app > (Output dir). Every methods exports successfully, but the resulting App is not working (the app starts, but the Extension is not loaded neither recognised). I've also noticed that pluginkit -m -v shows me the Extension as loaded and active every time I lanched Product > Archive, but the directory from which the Extension is loaded is non-existent: /Users/alessioscibilia/Library/Developer/Xcode/DerivedData/Hive-CutAndPaste-fpfzypnezgtfzlcugohasvonofbf/Build/Intermediates.noindex/ArchiveIntermediates/Hive-CutAndPaste/InstallationBuildProductsLocation/Applications/Cut & Paste.app/Contents/PlugIns/Cut & Paste Finder Extension.appex I guess it's a temporary directory used by the Archive process. When I use the Extension just after Archiving, it works but is not fully functional: icons and localization strings are missing. So I always removed the Extension (with pluginkit -r) before every Exporting from the Archive. As just said, launching every Exported app results in Extension not loaded. I don't know what to do anymore, I've run out of ideas. Thank you again for every further suggestion

Finally I solved it like this: I changed the Extension's Bundle ID I regenerated all the certificates and Provisioning Profiles, checking all options applicable to macOS The software works almost perfectly now, but it still crashes randomly from time to time. I suspect there might be some leftover "junk" in the registry used by pluginkit, due to all the testing I did. Anyway, now I need to figure out how to receive crash reports from users. Is there a guide you’d recommend? Thanks a lot!