Pixel shimmering and glitching in Godot 4 (see image and gif)

[past fable]

https://gyazo.com/df47ad08833c0af58a2f3c4633eb1ac9
Hi, since porting to Godot 4 (and not prior to) I've experienced a bunch of pixel shimmering in camera/sprite movement and uneven pixel positioning even when the camera is static - see the eye in the image. The game's base resolution is 320x180 and I usually run the game in a 960x540 window although the issue is consistent across different resolutions & when using fullscreen. The window stretch mode is set to canvas_items mode with keep aspect ratio and 1.0 scale.
I have Use GPU Pixel Snap and Use Pixel Snap enabled. I've tried the Snap 2D Transform and Vertices options but the problem persists - ideally I don't want to use these anyway as I don't want the game to feel jittery. I even switched the renderer from Vulkan to compatability and it still persisted. Seeing as I didn't face this issue at all in v3.5 I can't think of anything else I could do to fix this...

you can see the distortion here too on the quit button on its top border; not how it appears in the editor

[past fable]

Pixel shimmering and glitching in Godot 4 (see image and gif)

[sick saffron]

Everything look good

[past fable]

Update - Godot4 beta17 is having some sort of glitch where the window was being sized to 970x550 rather than 960x540 for no evident reason - it would also seem i was mistaken with fullscreen mode as it was working correctly when i went back after posting this. my fix at this time for windowed mode is via the config system i was using in 3.5 which i had yet to fix when posting; my code force sets the window size based on the config settings, meaning the initial inaccurate window size is overriden. I wouldn't consider this issue closed since having to hardcode overwrite a value that I never set in the first place is inefficient and shouldnt be the case