ADDITIONAL SYSTEM INFORMATION :
> uname -a
Linux 0be9c4498283 6.12.5-linuxkit #1 SMP Tue Jan 21 10:23:32 UTC 2025 aarch64 aarch64 aarch64 GNU/Linux

> java -version
openjdk 24 2025-03-18
OpenJDK Runtime Environment (build 24+36-3646)
OpenJDK 64-Bit Server VM (build 24+36-3646, mixed mode, sharing)

A DESCRIPTION OF THE PROBLEM :
Enabling **canonical equivalence** causes a pattern to not match a string with a **variation selector**.
`Pattern.compile("^[^/]*\\.[^/]*$", Pattern.CANON_EQ)` does not match a string containing a variation selector (e.g., `U+FE0F`).
While `Pattern.compile("^[^/]*\\.[^/]*$")` matches the string.

The workaround is to remove variation selectors from the string.

The described bug is the root cause of the following problem:
On macOS, when a path matcher is created using the pattern `glob:*.*`,
it gets converted to the regular expression `^[^/]*\.[^/]*$`,
and the `Pattern.CANON_EQ` flag is passed during pattern compilation.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1. Compile pattern using the expression ""^[^/]*\\.[^/]*$" and the flag `Pattern.CANON_EQ`.
2. Match a string that contains a variation selector

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The pattern matches the string
ACTUAL -
The pattern does not match the string

---------- BEGIN SOURCE ----------
import java.util.regex.Pattern;

public class Main {
    public static void main(String[] args) {
        // there is the variant selector (U+FE0F) after the heart emoji
        var strWithVariantSelector = "❤️ file.txt";

        var expr = "^[^/]*\\.[^/]*$";
        var pattern = Pattern.compile(expr);
        var patternWithCanonEq = Pattern.compile(expr, Pattern.CANON_EQ);

        var patternMatches = pattern.matcher(strWithVariantSelector).matches();
        var patternWithCannonMatches = patternWithCanonEq.matcher(strWithVariantSelector).matches();

        System.out.println(patternMatches); //true
        System.out.println(patternWithCannonMatches); //false
    }
}
---------- END SOURCE ----------