I came across a need to select all matches in VS Code. This was the procedure, thanks to stack overflow. I altered them for Mac, since that’s what I was using. For Windows/Linux, substitute CMD with CTRL

1. CMD + F
2. Type your search string
3. CMD + SHIFT + L to select all occurrences found (max. 999)
4. ESC (or close search dialog with top-right X)
5. CMD + C
6. Open new file
7. CMD + V

Works great! It’s a way for me to easily get ONLY my search string from a file and discard the rest.