How NotchStar detects what you copy
NotchStar finds out about your copies by asking the Mac’s clipboard whether it changed, about every half second. The clipboard keeps a change counter that goes up each time anything is copied. When NotchStar sees the counter move, it reads what is on the clipboard and adds it to the list.
What happens on each check
- NotchStar compares the counter with the last one it saw. If it is the same, it stops there and costs almost nothing.
- If a password manager marked the copy as concealed, it stops and records nothing.
- If the copy holds files from Finder, it records the files.
- Otherwise, if there is text, it records the text.
- Otherwise, if there is an image, it records a reduced copy of the image.
That order is why a Finder copy shows up as a file and a spreadsheet copy shows up as text. See images and files.
It keeps checking with the notch closed
The check runs while NotchStar is running, whether the notch is open or closed. That is how it can show a copy you made a minute ago when you open Clipboard.
Why polling
The Mac does not tell apps when the clipboard changes, so a half second check is the usual way clipboard tools work. Two copies within half a second of each other can mean only the last one is seen.
Limits
Copies made before NotchStar started are not read. See that page. The tool is on the Clipboard feature page.
