The one I posted are all within an Examples Macro Group, so they wont pollute your existing macros, and disabling that macro group will ensure they don’t execute.
Also note a couple things for this sort of question:
- Importing macros can be undone, so you can import the macros and then undo it.
- If you quit and relaunch the Keyboard Maestro editor, you can then use the File ➤ Revert Macros menu to revert to the macros as they were when you launched the editor, so you can import macros and then back out by reverting back to “At Editor Launch”.
That said, if you import macros, the macros can run immediately (for example , if triggered by something like Periodic Every Second), so if you are importing a macro from an untrusted source, it can execute something pretty much immediately - this is something to keep in mind if you don’t trust where you are getting the macros from. You can safeguard yourself by holding all the modifiers (Command,Option,Shift,Control) down when importing macros (which will import them disabled), or by relaunching the Keyboard Maestro editor (as above) and then quitting the Keyboard Maestro Engine so no macros are run, and then importing the macros. Then you can look through the macros and verify their behaviour and/or disable them and then relaunch the Keyboard Maestro Engine.