.{0,3}any Unicode character (except for line terminators), repeated between 0 and 3 times
.{0,5}any Unicode character (except for line terminators), repeated between 0 and 5 times
g modifier: global. Finds all matches instead of stopping after the first
m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string