Win+R is for single-line text, though if you have a browser focused, you can use the address bar for this too - press CTRL+L to focus it, then usual CTRL+V CTRL+A CTRL+X.
Notepad is for multi-line text.
EDIT: While the address bar trick may be slightly more convenient than Win+R (and the easiest thing to do on Linux), keep in mind that whatever you paste there will likely end up recorded on someone else's servers. I bet this was a major driver for integrating previously separate address bar and search bar, and adding "search suggestions" function...
Notepad is for multi-line text.
EDIT: While the address bar trick may be slightly more convenient than Win+R (and the easiest thing to do on Linux), keep in mind that whatever you paste there will likely end up recorded on someone else's servers. I bet this was a major driver for integrating previously separate address bar and search bar, and adding "search suggestions" function...