 p;
    }
    checkGetBufferSubData(gl.NO_ERROR, "srcData");

    debug("");
    debug("write-unbind-fence-wait-bind-read");
    gl.bindBuffer(gl.COPY_WRITE_BUFFER, null);
    gl.bindBuffer(gl.ARRAY_BUFFER, readbackBuffer);
    gl.copyBufferSubData(gl.COPY_READ_BUFFER, gl.ARRAY_BUFFER, 0, 0, 8);
    gl.bindBuffer(gl.ARRAY_BUFFER, badBuffer);
    await fence();
    gl.bindBuffer(gl.COPY_WRITE_BUFFER, readbackBuffer);
    checkGetBufferSubData(gl.NO_ERROR, "srcData");

    debug("");
    debug("write-fence-wa