Custom Attribute - Regex Expression Help

Hi!

I am looking to filter on a custom attribute in a canvas audience paths, but I want to do a contains statement.

I am trying to reference multiple attributes with out having to list each specific value as the trigger. The attribute naming convention works were I could use contains.

Thinking I can use a targeting filter where custom attribute matches regex. However, are there any special characters that need to be added to/around "signup" in the attribute value?

Thanks!