tell application "System Events"
file of first process whose frontmost is true
set frontApp to text 1 thru -5 of (get name of result)
end tell
set fullClipText to (the clipboard as text)
try
set maybe to ((choose from list paragraphs of fullClipText) as text)
if maybe is not "false" then
set the clipboard to maybe
delay 1
tell application frontApp
activate
tell application "System Events" to keystroke "v" using {command down}
end tell
delay 1
set the clipboard to fullClipText
end if
end try
It doesn't use the name of the process which may be different of the application's name.
It doesn't change/reset the clipboard's contents if the user decide to Cancel.