Grid squares on the mbtiles

[kovalartem]

Hello All.
I am trying to export data from PostGIS table using tilelive-copy:
./tilelive-copy bridge:///tmp/poly.xml countries.mbtiles --maxzoom=7 --bounds=-180,-90,180,90

poly.xml.zip

After this is done, I've imported data to qGIS using plugin "Vector Tiles Reader" and observed some kind of grid squares:

How can I remove them? Polygons are splitted inside of this squares, checked this after data was exported to GeoJSON:
countries.geojson.zip

Please, help.

[jachym]

If I understand this correctly, this is desired feature of the tilelive - to create tiles. Not sure, how you rinput data do look like, but maybe QGIS can open it directly?