Wireshark Extcap plugins all Wireshark to configure and capture from devices that are not natively supported by the application. There are two directories where Wireshark looks for these plugins, and you can discover those directories in the About dialog, found in the Wireshark menu.
We recommend installing osciumdump in the Personal Extcap folder, as the Global Extcap folder is overwritten when Wireshark updates are installed. Double click on the link in the About dialog, and you will be prompted to create the folder if it doesn't already exist, and then the Finder will open the folder.
Using the terminal, chmod 755 osciumdump-darwin-arm64 to make the plugin executable. Copy osciumdump-darwin-arm64 to the extcap folder. Double click osciumdump-darwin-arm64 to run it.
MacOS will display a warning about the executable potentially containing malware. It does not. In fact, the executable is signed with Oscium's developer key and notarized by Apple. However, MacOS Gatekeeper is unable to evaluate standalone executables. Hopefully Apple will fix this issue in a future update to MacOS.
Click Done on the Gatekeeper warning, and then go to System Preferences to enable osciumdump to run.
Selecting Open Anyway will prompt for Administrator confirmation. Even after selecting this option, MacOS will still check one more time that you really, really are OK with using osciumdump.
Clicking Open Anyway in this double-check dialog will finally result in osciumdump running. As a standalone executable, all it does is open a terminal window and print:
extcap {version=1.0}{help=}
interface {value=autodetect}{display=Oscium remote capture (0 detected)}
Saving session...completed.You can close the terminal window, and the extcap folder window in the Finder, osciumdump is now active and will be visible in Wireshark. Click the gear icon to the left of the interface to change capture settings. osciumdump supports simultaneous capture from multiple WLAN Pi Go devices