I am using fedora 25 but I think this is a general behavior on unix system.
ctrl+r in a command-line environment I can start to type in and anything I type will get to be matched backward in the invoked command history of the current user. This helps a lot to rapidly find a command and not type it again.
I like to optimize when it comes to my environment, but sometimes when I am fast I found the prompt a bit confusing because everything is white, for instance if I type
find during the reverse-i-search, the prompt will output something like that,
(reverse-i-search)`find': find . -type f -name '*.h'
Is there a way to color the part before