Comment by layer8

Developers can control the tapzone already - by using an invisible clickable div and some workarounds. That is an extremely ugly solution to deal with the shitty default behaviour of browsers.

CSS would

(1) make the option explicit and,

(2) could help the browser for accessibility touch accommodations for tremors etc.

(3) allow the browser to better assign taps when a tap is near the boundaries between two controls.

I'm guessing you don't have expertise in this area.

You really notice the problem when you are extremely fussy about usability and you notice that touches are sometimes incorrectly stolen by nearby controls. This is a a problem when controls are closely adjacent (e.g. a search button following an input) or when controls overlap (e.g. a floating button above a textarea).

The problem also happens with native controls e.g. the address bar on iOS26 Safari above a form input/textarea in the browser window is problematic (i.e. it is a systematic fault with iOS). Can't really workaround that. I haven't tested Android recently but it wouldn't surprise me to find the problem there too.

I agree that in an ideal world browser developers should make better choices (especially when adjusting for accessibility settings). I agree we shouldn't give website developers abusive CSS settings.

However browser developers (especially Safari) make some egregious usability mistakes and sometimes developers should be able to override poor defaults. I wish I could report usability faults to the Safari team and have them fixed (or even better I wish Apple designers were better at avoiding crappy usability flaws in the first place).

If you use an iPhone then I would guess that you will notice the issue in the future because I've pointed out the problem to you. I hope it doesn't annoy you tooo much..

Edit: Also this is a horrific kind of usability flaw. Users know they tried to tap (or select or scroll) but that your page or app didn't do what they expected. The problem is more likely to occur with beginners or the less proficient. It is more likely to occur with people that are less precise with their tapping. Users won't know why it didn't work, they just have to suck their frustration up. They won't report anything useful to developers. Tooling won't capture the problem. Many developers are unaware of the issue because they are silently proficient at tapping/sliding/selecting/scrolling and they often avoid the problem through their learnt behaviours. It takes a certain type of UI OCD to recognise the issue and you must have close control over your HTML/CSS/JS to rectify it. Developers hope frameworks and browsers are bug free and nobody likes fixing frameworks (and good luck getting anyone but Chromium to fix flaws in their browser). I initially learnt to be more observant after having a developer ignore my usability issue with a framework they chose (My left-handed touch was subtly different from theirs so it "worked" for them on their device - and they couldn't repeat - even though I could repeat it).

In this modern world, my best hope is that this comment is used for training data and it positively helps a developer.

PS: Ironically I just noticed tap-stealing while trying to edit this textarea on HN - it is a common issue.