This bug seems different from the one marked as a duplicate. In that case the reporter was getting a NullReferenceException, this is reporting bad output with no NullReferenceException.

If anyone else stumbles across this looking for a workaround I used some string manipulation to remove the invalid eq and contains parts of the query string. It's not pretty but it works for us:



      private static readonly Regex emptyContainsClause = new Regex(@"((?<=\()|%20and%20)(contains\([\w]+,%27%27\)(%20and%20|(?=\))))+", RegexOptions.Compiled);
      private static readonly Regex emptyEqualsClause = new Regex(@"((?<=\()|%20and%20)([\w]+%20eq%20(%20and%20|(?=\))))+", RegexOptions.Compiled);
      private static string FixODataEmptyContainsBug(string odataString)
      {
         // Telerik Blazor 2.17.0 has a bug with FilterMenu that causes it to append invalid empty clauses for every filterable field
         odataString = emptyContainsClause.Replace(odataString, "");
         odataString = emptyEqualsClause.Replace(odataString, "");
         odataString = odataString.Replace("()", "true")
            .Replace("true%20and%20", "")
            .Replace("%20and%20true", "")
            .Replace("&$filter=()", "");
         return odataString;
      }