I also created this AppleScript:
tell application "Safari"
set windowName to name of window 1
set windowURL to URL of document 1
end tell
set the clipboard to "[" & windowName & "](" & windowURL & ")"
I wouldn’t use TextExpander for this one, I’d use Keyboard Maestro instead because you can set a trigger for when it is run. I also made the final output into a markdown link for easier posting as a link.