Kilian Valkhof

I build tools for developers and designers: Polypane.app, fixa11y.com, superposition.design and fromscratch.rocks | Electron governance member | He/him

website: https://kilianvalkhof.com
Polypane: https://polypane.app

Public Key

npub129a4uafwfs4nfdxmezmxvfvh9apd4zs65uyj0jrdh79yezcgfq7slm2fex

NIP-05 Address

kilian_at_mastodon.social@momostr.pink

Profile Code

nprofile1qqs9z767w5hyc2e5kndu3dnxyktj7sk63gd2wzf8epkmlzjv3vyys0gprpmhxue69uhhyetvv9ujumt0d4hhxarj9ecxjmntf6eqav

Publishing to

relay.momostr.pink

Author Public Key

npub129a4uafwfs4nfdxmezmxvfvh9apd4zs65uyj0jrdh79yezcgfq7slm2fex

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Last Notes

2026-01-28 15:22:26 UTC

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🙏 This is such a good read, you added work to my backlog

2026-01-22 13:27:38 UTC

Understanding the fundamentals of CSS layout
When devs say that CSS is hard, they're usually talking about CSS layout. What often gets omitted is that developers are assumed to understand and effectively use CSS without being taught how it works in the first place.
https://polypane.app/blog/understanding-the-fundamentals-of-css-layout/

2026-01-14 09:51:02 UTC

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Eric

2025-12-18 11:49:59 UTC

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yeah this is is a scam and you can ignore it.

2025-11-20 13:25:18 UTC

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Is it statistically significant?

2025-11-20 13:16:56 UTC

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Sara out here A/B testing Flu strains.

2025-10-30 10:13:36 UTC

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that said, if PVV ends up being the biggest party (which it could end up, albeit with a few thousand votes difference) they have first opportunity to try to form a coalition. PVV, VVD, JA21 and CDA would get you to 50% to you need a smaller party like BBB or FvD to get a majority.
Some people might say CDA wouldn't join that coalition, but I could see it happen.

2025-10-30 10:09:07 UTC

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on paper yes, but the most reasonable coalition of D66, CDA, VVD and PVDA (broadly centre-left) has been ruled out multiple times by the VVD over the inclusion of PVDA.
The party leader of PVDA resigned last night though, so the hope is that gives the possibility for VVD to walk back that hard line.
The other option is centre-right D66, VVD, CDA with JA21 and either BBB or CU, neither of which seem likely to want to rule (and I strongly hope D66 isn't entertaining JA21)

2025-10-30 09:56:57 UTC

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D66 is best described as progressive, VVD is 'old-style' right wing but got significantly more populist in recent years.
PVV lost but is still the largest/second largest, Ja21 and FvD both gained seats. All three are right-wing lunatics with murky ties to russia.

2025-10-27 15:42:33 UTC

"Write accessible code or get sued!" This ain't it
"Write accessible code for SEO." No
"Write accessible code for AI." Nooo
"Write accessible code for blind people." ...better
"Write accessible code cause you're a god-damn professional that takes pride in their work." Now we're talking.

2025-09-30 08:32:51 UTC

This was a tiny feature to implement, but I get so much value out of color coding the address bar depending on the domain I'm working on.
Tab customization in Polypane: https://polypane.app/docs/tab-customization/
https://files.mastodon.social/media_attachments/files/115/292/316/547/847/516/original/c0bf3e5d89dc2512.png

2025-09-22 07:31:31 UTC

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our library has 'ebook lending' through the same DRM stuff as Kobo so my kid who has my old Kindle can't use it out of the box and we also have to use Calibri, so I'm familiar.
It's annoying to have to jump hoops for something you're allowed to do.

2025-09-22 07:25:07 UTC

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this book should've been a website!

2025-08-25 15:49:11 UTC

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Really? You always struck me as an even-keeled developer.

2025-07-23 08:46:13 UTC

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Mastodons social media previews are downloaded asynchronously in the background by the server so them showing up is dependent on the server and how often (if ever) it runs that task.
Your tags look correct Sara!

2025-07-16 08:18:03 UTC

@npub1wpv…rz2s regarding naming of https://piccalil.li/blog/a-revisit-of-the-every-layout-sidebar-with-has-and-selector-performance/ have you considered "unholy grail"?

2025-06-04 09:03:13 UTC

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you know wcag.lol is still available

2025-06-03 07:35:40 UTC

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dutch one! 🍾

2025-06-01 12:53:18 UTC

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yes, but it was code in Polypane I broke ;)

2025-06-01 12:41:41 UTC

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well this makes me feel validated for when I broke Polypane with the exact same behavior :D

2025-05-07 18:01:27 UTC

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I have no idea what that is, but it's definitely the worst name for a thing I came across this month.

2025-04-18 11:20:11 UTC

me: man I gotta make sure all these icons line up correctly in my UI or people will complain!
gmail: lol ship it
https://files.mastodon.social/media_attachments/files/114/358/694/744/496/904/original/8ac828a22ffe9db7.png

2025-04-09 09:06:20 UTC

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protruding new stacking context means that stacking context in stacking contexts that would normally sit behind other z-indiced elements are now pushed forward more, and that 3d transform takes precedence.
I'm not sure if I should/want to change that.

2025-04-09 08:58:43 UTC

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neatly stacked (New stacking contexts get a large jump, z-index values inside a stacking context get a smaller jump)
https://files.mastodon.social/media_attachments/files/114/307/172/785/038/709/original/66f1c974bfb335de.png

2025-04-09 08:42:59 UTC

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Guess I have some kinks to work out! (the red borders mean they're detected as stacking contexts but they're not moved forward)
https://files.mastodon.social/media_attachments/files/114/307/111/529/869/208/original/81e89d0e220e0903.png

2025-04-09 08:28:06 UTC

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nerd-snipe successful.
https://files.mastodon.social/media_attachments/files/114/307/051/705/332/233/original/0f21da27f9af59a8.mp4

2025-04-09 05:54:53 UTC

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sounds like a challenge

2025-04-03 09:35:56 UTC

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cause otherwise the kids sneeze in our faces

2025-04-03 09:31:14 UTC

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the default response to that in our house isn't "bless you", it's "Elbow!"

2025-04-03 09:29:50 UTC

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oh geez. good luck out there.

2025-03-18 12:29:52 UTC

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may I propose apologizing with "I'm sorry you were annoying"? ;)

2025-02-13 15:23:46 UTC

Polypane 23.1 is out! 🥳
- New Event badges and event listener tab in the elements inspector
- A new marker tool in the screenshot editor
- Shortcuts for all screenshot annotation tools
- Keyboard accessibility improvements
- a ton more
Check it out: https://polypane.app/blog/polypane-23-1/

2024-12-31 19:44:29 UTC

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basically! Though it’s been greatly reduced in recent years imo. Still, can’t wait for it to be banned.

2024-12-23 14:52:48 UTC

Three years ago I added a ticket to my backlog to add support for the `layer` attribute on <link rel="stylesheet"> and <style> once that landed in engines.
Did we just decide to ...not add that anymore?

2024-12-13 19:13:17 UTC

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*high five* grumpy parents assemble!

2024-12-06 09:09:06 UTC

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Sara we were abusing that long before React was a thing.

2024-12-06 08:50:15 UTC

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it's normal to take yearly photos at the dentist here too.
I'm sorry they make you go through that.

2024-12-05 12:30:05 UTC

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on the one side we have boomers being fed garbage through TV, on the other side we have TikTok feeding garbage to Gen Z.
What's the garbage we're getting but not recognising as such?

2024-12-02 08:48:25 UTC

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yeah ceiling placement, like a lamp

2024-12-02 08:34:45 UTC

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do you want to heat up the space, or yourself? Because if the latter an infrared panel might be interesting!

2024-11-22 16:16:01 UTC

When I am President, it will be illegal for companies to email you just to say they have a message for you and not include that message in the email they’re already sending you.

2024-11-14 13:54:34 UTC

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because a lot of people don't realise that setting all: unset means they have to add back in a lot of things that aren't immediately visible [to them]

2024-11-14 13:24:15 UTC

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...yeah but I can't start a tooltip with "In this essay, I will..." 😬

2024-11-14 11:57:17 UTC

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tada :D
https://files.mastodon.social/media_attachments/files/113/481/178/745/382/047/original/6bbdd091a5b09be9.png

2024-11-07 12:57:31 UTC

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is it because PDFs are only for super serious business people in suits?

2024-11-05 08:09:31 UTC

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maybe even just a little exclamation icon next to use of 'all'?
problem there is that I think the CSSOM unrolls it to literally all properties 🤔 I'll investigate!

2024-11-04 09:04:29 UTC

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Yes!
old situation: Twist knob. Done.
new situation: Tap the icon to select the heater it is on. Tap again because it didn't register. Tap the minus icon. Wait because otherwise it doesn't register. Tap the minus icon. Wait because otherwise it doesn't register. Tap the minus icon. Wait because otherwise it doesn't register. Tap the minus icon. Wait because otherwise it doesn't register. Done.

2024-11-04 08:41:47 UTC

Buttons are superior to touch interfaces in almost all places.
Our previous gas stove and oven had buttons and dials and it was clear, easy & quick to operate.
Our new induction stove and oven uses touch. Everything takes easily three times as long.
https://spectrum.ieee.org/touchscreens

2024-11-04 07:53:12 UTC

I've never used `all: unset` and not regretted it.

2024-10-31 12:45:02 UTC

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It could've said "made by human hands" which would've been both more correct and worse.

2024-10-02 07:37:56 UTC

You hate web components because they don't integrate into your framework
I hate web components because they're an absolute PITA to make inspectable.
We are not the same.

2024-09-27 14:38:59 UTC

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i meant all of the above, and yeah tbey’re checkboxes so I checked all three!

2024-09-27 13:36:19 UTC

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Missing the "Yes" answer, but primarily Linux.

2024-09-23 08:59:51 UTC

I love agreeing to the xcode terms of the software license agreement before I can see the output of `git status`.

2024-09-18 14:27:03 UTC

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So in Polypane you just hover over an element and hold Alt/Option ;) it shows the accName and the accRole directly from the generated accessibility tree.

2024-08-27 09:43:16 UTC

Every day more and more people tell me they found Polypane through conversations with ChatGPT, Claude etc.
I feel like I have zero influence on that happening (is it just SEO translating into AI indexing?) and yet it seems a pretty reliable way for people to find Polypane.