Shotcut introduced proxy files in version 20.06 onwards. This is to reduce lag for faster smoother editing experience.
I made this video to show you how to set up proxy files in editing.
You will enjoy better performance for smoother faster editing with reduces lag. Watch the video below where you will learn the 2 ways to use proxy files.
Less frustration. More videos created faster.
Let me know how it work for you.
Sign up for my Shotcut training here.