bug: `isKeyDown` and `isButtonDown` get stuck when cmd-tabbing on mac

[Stanko]

Bug Description

When holding a key or a button and use cmd-tab to change to other application, isKeyDown() (or isButtonDown()) get stuck and report astrue until the key/button is pressed again. I created a small example at playground where you can test it.

I'm not sure if this is a mac only issue.

Version

4000.0.0-alpha.27

Playground Link

https://play.kaplayjs.com/?code=eJydkU9rwjAYh%2B%2F5FC%2F1YAK1tiA7KM6LN4%2By09ghS2ItcUlIU7QMv%2FvyR6EIRVxuCb%2Fn9yRv5nPYO2pdCxSUOENNfwRiWrUOJKxBUnOiPf5F4Nc3ZbK2ulN8CdNJFdc0R1eyQjfkJA4uUAXlHH%2FKwugWy4IJ5YTFJJ7OqkWZQ0lIHmKKHbXFWUpk8UwbyhrX47JYxL0TF4ez0JyRL69KJtvUx2eq%2F5li81DVmSceb5m9vezpzFDC9VmNa16sDmWpHPmI%2BjCcOoExgfU7pK8M47zDUdu0O9FvPXcfNWyggiX44lUk4ljGkNvMHpnOjAHh8Y%2FpcOuxfHrRkLgShNAfZ3LQmw%3D%3D&version=4000.0.0-alpha.27

Extra information

No response

Summary

• Fixed in v4000
• Fixed in v3001

[dragoncoder047]

I'm on MacOS 26 and don't have this issue

[Stanko]

I guess you mean 16? I just saw they jumped to version 26 😅
I'm on 15.7.4 (24G517)

Here is a video of it happening on firefox and chrome. I added on-screen keyboard so you can see keys I'm pressing.

button-press.mp4

[dragoncoder047]

I think this is probably an OS problem not a KAPLAY problem, you can trigger it by clicking off of (unfocusing) the game window while the keys are being held

Screen.Recording.2026-05-06.at.7.01.24.PM.mov

[Stanko]

I don't think it is a browser/os bug. Because key up event didn't happen while document/element was focused, it doesn't trigger.

Here is a HTML/JS reproduction. The fix is to clean all of the pressed states when window looses the focus.
https://codepen.io/stanko/pen/dPOGGjV

[beemdvp]

Wanted to try this on linux too and its the same behaviour haha. Feels like a key logger that players may find and could lead to some unwanted behaviour