I can enter a command:
$ echo hello hello
Then search for it with Ctrl+R:
(reverse-i-search)`h': echo hello
Then sometimes the search will fail:
(failed reverse-i-search)`hz': echo hello
Can I somehow color the "failed reverse-i-search" part of the display? I would prefer if it was red text to contrast with normal white text. That way I can quickly tell that a search has failed.