Strange graphic artifact on specific Android tablet

[Vasco]

I've noticed a graphic glitch when testing my game on a Sony Tablet S.

It's an old tablet from 2011, so it's not that important, but I'm afraid the glitch may appear on other devices.

Basically there's a strange fussy pixelated effect which is particularly noticeable on black lines which should be completely straight (image scaled 200%):

I've tried changing anti-aliasing on and off, but it doesn't make much of a difference.

I'm wondering if anyone here has seen this before or has a suggestion for fixing this? Thanks in advance.

[seiren]

I also have similar problems.
The model is Sony Xperia XZ.
I have only this device.
So I do not know if it happens with other devices.
Please tell me if there is a solution.

[galoyo]

FlxG.stage.quality = StageQuality.BEST; might work.

[seiren]

It did not work.
There is no difference.

I tried a couple of other things.
And I found that when I turned off the fullscreen I got much better.

<window if="mobile" orientation="landscape" fullscreen="false" width="0" height="0" />

[Vasco]

For me neither changing the stage quality nor setting fullscreen to false made any improvement.