The security rules editor supports the regular expression operator "matches". This operator is case insensitive and returns results that match your expression, irrespective of case. Regex start and end anchors are implicitly added.
Syntax:
(EXPRESSION) matches (EXPRESSION)
Examples and results:
Example
Result
resource.name matches ".*yAp.*"
Evaluates all resources with names containing "yap" to True, irrespective of case.