QGIS » QGIS Application

After editing a feature in a PostGIS and trying to save the layer, QGIS gives the warning that it could not commit the changes to the layer. The following error in the PostGIS messages tab.

2019-03-03T18:18:05     WARNING    Erroneous query: UPDATE "Balance of Power"."timeline-countries" SET "main_rgb"='E1BE48',"border_rgb"='D9B023',"info_url"=E'{""}',"flag_url"=E'{""}',"predecessors"=E'{""}',"successors"=E'{""}' WHERE "feature_uuid"::text='e0471e92-82e6-484c-92e2-1538eb6e0adb' returned 7 [ERROR: invalid input syntax for uuid: "" 
             LINE 1: ...fo_url"=E'{""}',"flag_url"=E'{""}',"predecessors"=E'{""}',"s...
              ^
             ]

The column it is complaining about is predecessors, which in PostGIS is an array of UUID. The column is empty, but QGIS appears to be trying to save it as an array with a single empty string but that column for that row is empty (NULL).

The schema for the table is:

CREATE TABLE "Balance of Power"."timeline-countries" 
(
    geom geometry(MultiPolygon,4326),
    name text COLLATE pg_catalog."default",
    start_date date,
    end_date date,
    main_rgb character varying(8) COLLATE pg_catalog."default",
    feature_uuid uuid NOT NULL DEFAULT uuid_generate_v4(),
    country_uuid uuid NOT NULL DEFAULT uuid_generate_v4(),
    stripe_rgb character varying(8) COLLATE pg_catalog."default" DEFAULT NULL::character varying,
    border_rgb character varying(8) COLLATE pg_catalog."default" DEFAULT NULL::character varying,
    border_shade numeric DEFAULT 0.085,
    sovereign text COLLATE pg_catalog."default",
    type text COLLATE pg_catalog."default",
    info_url text[] COLLATE pg_catalog."default" DEFAULT ARRAY[]::character varying[],
    flag_url text[] COLLATE pg_catalog."default" DEFAULT ARRAY[]::character varying[],
    predecessors uuid[] DEFAULT ARRAY[]::uuid[],
    successors uuid[] DEFAULT ARRAY[]::uuid[],
    visible boolean DEFAULT true,
    alternate_name text[] COLLATE pg_catalog."default",
    full_name text[] COLLATE pg_catalog."default",
    full_names json,
    CONSTRAINT "timeline-countries_pkey" PRIMARY KEY (feature_uuid)
)
WITH (
    OIDS = FALSE
)
TABLESPACE pg_default;

I cannot edit several fields (info_url, flag_ur, predecessors, successors) in the form view for the feature that cannot be updated, but can do so for other features.