The clipboard manager has been available in Alfred for long enough that I regularly forget to use it. A recent project had me working in a large TaskPaper document. I wanted to collect several lines into one block and then move them to the end. There are several ways to do this, but of course I had to go down a rabbit hole on Alfred to solve it.
Make sure the Alfred clipboard manager is enabled:
Next, turn on the fast append feature:
The wording on that screen was a bit confusing to me. I imagined that I needed to select items in the clipboard manager and then append them together. That is not correct. Instead, when a block of text is selected in an application, hit CMD+C,C (hold the command key and double tap "C") to append the selection to the previous clipboard entry.
I like to separate the items with a newline character but there's also an option to separate with a space character.
This seems like something that Keyboard Maestro should be excellent at, but it's just not as simple as Alfred. If you really just want to use Keyboard Maestro, this should work:
The advantage with KM: it's pretty flexible and can theoretically do a lot more with the clipboard. I also think the Keyboard Maestro clipboard manager is very nice.