you can use Character. toLowerCase or Character. toUpperCase to make all to lower case or upper case and compare it.
Read moreHow do I make something optional in regex?
Optional Items
Read moreIs regex case sensitive?
By default, the comparison of an input string with any literal characters in a regular expression pattern is case sensitive , white space in a regular expression pattern is interpreted as literal white-space characters, and capturing groups in a regular expression are named implicitly as well as explicitly.
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