Join
First impression, I agree with the other guy, needs work.
Another bug is that if your regex is line enough to wrap to the next line, when you delete someone at the start of it, making it short enough to unwrap back into a single line, the cursor moves to the end of the regex and you start removing characters from the end instead of where your cursor was initially
RegEx v0.6.3
It never saves the sample text or substitution fields.
Very poor.