[Canvas Effects] Pixelated rendering mode + render size not working on mobile/android

[Dogo6647]

I'm trying to make a GBA-styled game where I need the canvas to "snap" to a resolution of 338x160 so that it looks convincingly low-res when sprites are scaled and rotated and every sprite pixel is equally squared (Scratch has a weird bug where low-res bitmaps look warped on some screens). So far these two blocks have worked pretty well for achieving the desired effect...

Until I tested my game packaged on my phone (packaged on PC works fine). I've tested several different mobile browsers (Brave, Built-in Jelly Browser on LineageOS, Via Browser, Google Chrome) and devices (Pixel 6a, Galaxy Tab A7 Lite, Honor 9X, Nexus 5, Galaxy S5, running android 14, 13, 10, 13, and 11 respectively (yes I custom rom a lot, that's why the N5 and S5 are running recent versions)), and none of them seem to do the render size thing at all.

This may sound kinda desperate but I absolutely need those blocks to work for the reasons listed above, as well as a graphical glitch in my tile-based scrolling level engine that causes a few gaps between the blocks to appear, which instantly gets fixed when those canvas effects are applied. If anyone needs more information, please let me know.

[GarboMuffin]

can you post a small example project for us?

[Dogo6647]

Sure! I actually happened to have a test project early in the development of the game to test just that. I just updated it to include some newer graphics from the game to better illustrate the issue.

Here's a screenshot of the test project on desktop showing a rotated sprite (how the low-res effect SHOULD look like):

And a 1-pixel line: (Again, on the desktop):

Whereas on my phone it looks like this:

Notice how when the sprite is rotated/scaled, pixels on the phone look unrealistically thin for a retro-styled game because of the blocks not working? Plus, here's the horrid gap glitch on the level tiles as I mentioned earlier:

Whereas on the desktop, it simply doesn't exist:

I think this has more to do with Scratch automatically rounding some decimals on the x/y value of the tiles without me telling it to do so, but the low-res effect doubles as a quick fix for that so it's still relevant.

Oh, and here's the test project's sb3 file, along with a packaged version of it:
gbaLFTest_ghissue.zip
To reproduce the issue, simply copy the packaged project to an android device and run it there.