

The screenshot is from my desktop with wide enough screen on Lemmy web (programming.dev).
The issue is one of scaling.
When I open the image without being resized into the website layout, it has the following visual pattern:
When I zoom out to 50% it looks (almost?) fine
Did you scale the source with ffmpeg? Do you have a visual pattern in your console background? The simplest solution would be to have a solid color as background. The second best to render a small enough size that it does not get resized in the browser.
At 1920x1038, it’s very big right now. I’m surprised the font is big enough to be readable. I assume you scaled it up or have a high dpi display resulting in this.
1, 2, 4, 5, 6 all look fine resized in the post and full size
3 looks fine full size but has slight visual artifacts resized in the post (check/square pattern)
I can barely see it on my monitor. So on worse monitors it may not even be visible. #272a31 vs #262b31
animated webp may also be an option