If your goal is a lightweight, "no-install" (portable) timer or clock, these are trusted, open-source options:
Even though version 1.42 is stable, it is not perfect. Here are common problems users face after the and how to solve them. i--- Portable Timekeeper 1.42 Download
“Write JavaScript to add a countdown timer feature to Portable Timekeeper” If your goal is a lightweight, "no-install" (portable)