Glad it was easily solved. You are starting to see the power of ‘regex’, over a ‘normal’ search mode. Normal will only allow for static information, whereas the ‘regular expression’ mode is essentially a formula created in such a way as to seek out those character patterns (even if changing). In ‘normal’ mode the \ is just a backslash and R is just a capital R. BUT, when you combine them under ‘regular expression’ they become a metacharacter, basically a ‘bit of code’ to mean something special to the regex engine. Under ‘regular expression’ mode we’d need to have \\R if we just wanted a backslash followed by a capital R. The first \ identifies what follows as being special (only certain characters can be special), however in this case because the second \ is already special it allows for it to become normal again.
Good luck and be sure to ‘seek’ out some of those supporting websites (and books) to learn more about “The Power of Regex” if you want to get better at it.
I was where you are now about 8 months ago, I’m still learning. There are many helpful ‘citizens’ on this forum who will also help. All we ask for is that you (the OP) give us enough information to help us to help you, and also we hope it will lead you onto learning more.
Terry