The Xero class makes reference to AccessTokenInterface from the League OAuth 2 client library. This interface wasn't added until version 2.4.0 in that dependency, but the composer file allows the installation of 1.|2. versions of this dependency, it should be >= 2.4.0 to ensure the interface is available.
The Xero class makes reference to AccessTokenInterface from the League OAuth 2 client library. This interface wasn't added until version 2.4.0 in that dependency, but the composer file allows the installation of 1.|2. versions of this dependency, it should be >= 2.4.0 to ensure the interface is available.