pgadmin4. utf8 bug report

I'm using binary:

- pgAdmin4: 1.1
- python: 2.7.12 (v2.7.12:d33e0cf91556, Jun 27 2016, 15:19:22) [MSC
v.1500 32 bit (Intel)]
- Flask Version: 0.11.

I have a table:

CREATE DATABASE test
WITH
OWNER = postgres
ENCODING = 'UTF8'
LC_COLLATE = 'Russian_Russia.1251'
LC_CTYPE = 'Russian_Russia.1251'
TABLESPACE = pg_default
CONNECTION LIMIT = -1;

with no any rows.

Table containg next columns:

ALTER TABLE public.machine
ADD COLUMN id integer NOT NULL;

ALTER TABLE public.machine
ADD COLUMN name character varying(256) COLLATE pg_catalog."default";

ALTER TABLE public.machine
ADD COLUMN vendor character varying(256) COLLATE pg_catalog."default";

ALTER TABLE public.machine
ADD COLUMN type_id integer;

ALTER TABLE public.machine
ADD COLUMN model_id integer;

ALTER TABLE public.machine
ADD COLUMN serial_number character varying(256) COLLATE
pg_catalog."default";

ALTER TABLE public.machine
ADD COLUMN software_version character varying(255) COLLATE
pg_catalog."default";

ALTER TABLE public.machine
ADD COLUMN matrix_id integer;

When i click 'backup' on menu:

Backing up an object on the server 'vending (127.0.0.1:5432)' from database
'test'...
Running command:
C:\Program Files\PostgreSQL\9.6\bin\pg_dump.exe --file "C:/Intel/123"
--host "127.0.0.1" --port "5432" --username "postgres" --no-password
--verbose --format=p "test"

Start time: Fri Dec 02 2016 17:56:05 GMT+0300 (RTZ 2 (зима))
'utf8' codec can't decode byte 0xe2 in position 30: invalid continuation
byte