--- a/testing/mozbase/rust/mozrunner/src/runner.rs
+++ b/testing/mozbase/rust/mozrunner/src/runner.rs
@@ -1,11 +1,10 @@
 use mozprofile::prefreader::PrefReaderError;
 use mozprofile::profile::Profile;
-use std::ascii::AsciiExt;
 use std::collections::HashMap;
 use std::convert::From;
 use std::env;
 use std::error::Error;
 use std::ffi::{OsStr, OsString};
 use std::fmt;
 use std::io::{Error as IoError, ErrorKind, Result as IoResult};
 use std::path::{Path, PathBuf};