[p5.js 2.0 Bug Report]: [p5.js 2.0 Bug Report]: _onblur doesn't fully reset keyboard state , keyIsPressed and keyIsDown() stay stuck after losing focus

[avinxshKD]

Most appropriate sub-area of p5.js?

• Accessibility
• Color
• Core/Environment/Rendering
• Data
• DOM
• Events
• Image
• IO
• Math
• Typography
• Utilities
• WebGL
• Build process
• Unit testing
• Internationalization
• Friendly errors
• Other (specify if possible)

p5.js version

2.x (main)

Web browser and version

Any

Operating system

Windows 11, but doesn't matter

Steps to reproduce this

Steps:

1. Open a sketch with keyboard input (see snippet below)
2. Click the canvas, then hold down the right arrow key
3. While still holding it, Alt-Tab to another window
4. Release the key in the other window
5. Switch back to the sketch tab

Snippet:

function setup() {
  createCanvas(400, 200);
}

function draw() {
  background(220);
  textSize(16);
  text('keyIsPressed: ' + keyIsPressed, 20, 40);
  text('RIGHT_ARROW down: ' + keyIsDown(RIGHT_ARROW), 20, 80);
}

After step 5, both keyIsPressed and keyIsDown(RIGHT_ARROW) are still true even though no key is being held. The key stays "stuck" until you physically press and release it again inside the sketch. Super annoying in any movement-based sketch

Root cause:
_onblur in keyboard.js only clears _downKeys but completely ignores _downKeyCodes, keyIsPressed, key, and code:

// what's there now
fn._onblur = function(e) {
  this._downKeys = {};
};

_downKeyCodes is new to 2.x _onblur was just never updated when it got added. Since keyIsDown() checks both maps, clearing only one of them doesn't actually fix the stuck state.,

Fix would be:

fn._onblur = function(e) {
  this._downKeys = {};
  this._downKeyCodes = {};
  this.keyIsPressed = false;
  this.key = '';
  this.code = '';
};

[avinxshKD]

What do you think of this?? pls assign if this makes sense @davepagurek @perminder-17

[ksen0]

Another great find. I tried to reproduce and I see that after step 5, keyIsPressed is True but RIGHT_ARROW down is False.

I also was able to observe this behavior when switching with a mouse, which shows that keyIsPressed stays true when it shouldn't:

arrows.mov

And when I alt-tab navigated away, I noticed that alt-tabbing away 2 times caused both values to become 'false' even when key remained pressed.

I found this behavior across all of 1.x as well as 2.x, so it's not a regression, though it could potentially be a bug to be fixed on 2.x, wdyt @davepagurek @perminder-17 ?

[avinxshKD]

Hey thanks for checking in @ksen0 and makes sense, You're right it's in both, looked at the code more carefully, the fixes are slightly different per branch though:

1.x (main): _onblur already clears _downKeys, so keyIsDown() does go false after blur. The only thing stuck is keyIsPressed (and key/keyCode), small fix i think.

2.x (dev-2.0): _onblur clears _downKeys but not _downKeyCodes, which is new in 2.x. keyIsDown() checks both maps, so it stays stuck. Plus keyIsPressed, key, code same as 1.x.

Two separate PRs make sense, one against main, one against dev-2.0. I can do both. If everything makes sense

Pls let me know if i am missing on something @ksen0 @davepagurek