[nh2]

With or without starship, one problem I have with zsh prompts is that when I press Enter, there is still a visible delay where for a fraction of a second, the cursor moves to the beginning of the next line.

This makes a nasty "flashing" effect.

If I keep Enter pressed, the cursor is permanently visible at offset 0 in the lowest line.

If the prompt is ultra-fast (e.g. plain root shell prompt on zsh), it happens less (e.g. only 50% of cases), but as soon as the prompt does anything, it's very visible.

I observe this with many terminals (gnome-terminal, wezterm, kitty, alacritty, xterm).

The only terminal I tried that doesn't have this problem is urxvt, where it looks perfect.

Video repro: https://nh2.me/flashing-cursors-on-newline.mp4

Why, and is there a way around it for those other terminals?

[nh2]

For Kitty I posted it on https://github.com/kovidgoyal/kitty/issues/8752, maybe we'll learn more!

[big_alfredo]

Try tweaking kitty's input_delay setting. For example: kitty --override=input_delay=10

[nh2]

input_delay doesn't seem to address this in general: Even when set to 50 (which is very noticeable), the cursor on the next line just appears with some delay.

None of the settings from https://sw.kovidgoyal.net/kitty/performance/ seem to affect its appearance.

[big_alfredo]

Interesting, In zsh I experienced the exact behavior you described and setting input_delay to 10 completely resolved it. To be fair, when testing my PS1 was simply '%m$ '.

I just benchmarked 'starship prompt' and when in a directory managed by git, it can take well over 10ms. I imagine with a more advanced configuration it would take even longer. urxvt must be doing something special.