Clipboard History and iTerm2

When pressing ⌘C to copy text in iTerm2, you may hear a macOS standard sound and notice your selection was appended to the previous item instead of being its own entry.

That happens through the confluence of two features: iTerm's Copy to pasteboard on selection and Alfred's Clipboard Merging. Turning off either of those will resolve the matter, as will remembering you don't need to ⌘C in iTerm when the selection feature is on.

You can find iTerm's option under its Setting… > General > Selection > Copy to pasteboard on selection and Alfred's in Alfred Preferences > Features > Clipboard History > Merging.