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using System.Text;
using System.Text.RegularExpressions;
public static class StringExtensions
{
    public static string ReplaceFirstInstance(this string originalString, string[] findValues, string replacementPattern)
    {
        string joined = string.Join('|', findValues);

        string pattern = $"{joined}";

        var r = new Regex(pattern, RegexOptions.IgnoreCase);

        string updatedString = r.Replace(originalString, replacementPattern, 1);

        return updatedString;
    }
}
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