Problem details:

In osu!mania first keyline always misses no matter if I do it quicker or later its always says miss. I'm running osu lazer from flatpak
Video or screenshot showing the problem:
https://drive.google.com/file/d/1-h2dngVjZJPiYgJs28tq18W6OLdRQilI/view?usp=sharing

osu! version:2025.424.0-lazer

you're hitting WAYYY too early, causing a miss.

No, this is probably https://github.com/ppy/osu/issues/22488 which does not currently have any fix.