In Loupe Desktop you can copy the message or the stack trace by hovering over them and then going to the "copy" button that appears on the right. You're right, we don't have a "copy everything raw" option in Desktop.
We've added a "copy everything raw" option to Desktop. Now when you hover over an exception message a Copy All button shows up on the right.
This will ship in our next update of Loupe Desktop.
it would be nice if I could copy the complete "concatenated" stacktrace messages into the clipboard from the Exception tab. Currently I can only copy the header or the message of a certain exception. Normally I would like to have all inner exception messages as well. Or did I miss something?