firefox and chrome checking onfocusin support not working anymore on recent versions

[sweafa]

firefox 106.0.2 (64-bit) chrome 107.0.5304.63 (64-Bit)

line 8615 in jquery 3.5.1 (8647 in jquery 3.6.1) support.focusin = "onfocusin" in window; // this line is getting filled by false, therefore a fix would be applied starting at line 8813 in jquery 3.5.1 (8843 in jquery 3.6.1)

commenting out block: "if ( !support.focusin ) {" fixes issue at those browsers

i stumbled over this bug when suddenly all my jquery-ui dialogs with modal: true would not work anymore and threw error: Uncaught TypeError: doc.addEventListener is not a function

[mgol]

Thanks for the report. Does the issue you describe exist when jQuery UI 1.12.1 is used or only with jQuery UI 1.13.0 or newer?

Also, please provide a test case.

[sweafa]

I tried with those both versions: 1.12.1 and 1.13.2. I infer that it probably has to do with jquery or firefox/chrome versions (did they drop support for window.onfocusin ?) and this bug report is created wrongly here. but anyway i could not recreate the issue in a test case. maybe it has something to do with ajax injected script. my project also is not hosted public, so i cant provide that either. i will once again try to setup a test case.

[sweafa]

best i could manage was this: https://codepen.io/sweafa/pen/RwJPKRx but seems more like https://github.com/jquery/jquery/issues/5104 and https://github.com/jquery/jquery/issues/5015

in my project the hidden div + dialog modal comes from ajax injected script

[mgol]

Firefox & Chrome never supported window.onfocusin and they have always got the fallback. We've removed the fallback in https://github.com/jquery/jquery/pull/4362 which will land in jQuery 4.0.0.

I tried your test case but I don't see any errors, either in Firefox 106, or in Chrome 107.

[sweafa]

yeah sorry about that testcase, i am not able to reproduce it on codepen. ah, so its ok that those browsers always get the fallback. then my first assumption was utterly wrong.