Yup, this is very surprising... On my machine the threshold is `setTimeout(..., 9)`. Safari 18.5, M1 MacBook Air
From the JS side, it works as expected (logging .textContent shows "blocking").
Even if you trigger a sync layout in JS (with .getBoundingClientRect()), the UI isn't updated until after the blocking code returns.
It looks like they over-optimized the rendering scheduler.
Ьλ∂λ
npub1lk…g4a7c
2025-09-04 15:58:43 UTC
in reply to nevent1q…92vu
Author Public Key
npub1lkxwap55syxrcz9d4759xx4hs7mw226x3elnf9nrvc45u4tx8hgseg4a7cSeen on
wss://relay.momostr.pinkPublished at
2025-09-04 15:58:43 UTCEvent JSON
{
"id": "76b5aafc00261c36fd74cd4c15461abb16340253a2ec58d607aa50bb7b076e0a",
"pubkey": "fd8cee8694810c3c08adafa8531ab787b6e52b468e7f349663662b4e55663dd1",
"created_at": 1757001523,
"kind": 1,
"tags": [
[
"p",
"fd8cee8694810c3c08adafa8531ab787b6e52b468e7f349663662b4e55663dd1"
],
[
"p",
"7a7a0978cc46ef7fd548fb125e51c04de7d4ca639417a21b56aa95e3711c0b38"
],
[
"e",
"511a348a2356c335fdd317cd6f09497c4d81357f276885242ffb6b72e60f122a",
"",
"reply",
"7a7a0978cc46ef7fd548fb125e51c04de7d4ca639417a21b56aa95e3711c0b38"
],
[
"proxy",
"https://mamot.fr/@pygy/115146851835082651",
"web"
],
[
"e",
"d8944085c3ef9fd23238020db369b9e39307f03b3a8a3d75d1456f9dec31ed14",
"",
"root",
"7a7a0978cc46ef7fd548fb125e51c04de7d4ca639417a21b56aa95e3711c0b38"
],
[
"proxy",
"https://mamot.fr/users/pygy/statuses/115146851835082651",
"activitypub"
],
[
"L",
"pink.momostr"
],
[
"l",
"pink.momostr.activitypub:https://mamot.fr/users/pygy/statuses/115146851835082651",
"pink.momostr"
],
[
"-"
]
],
"content": "Yup, this is very surprising... On my machine the threshold is `setTimeout(..., 9)`. Safari 18.5, M1 MacBook Air\n\nFrom the JS side, it works as expected (logging .textContent shows \"blocking\"). \n\nEven if you trigger a sync layout in JS (with .getBoundingClientRect()), the UI isn't updated until after the blocking code returns.\n\nIt looks like they over-optimized the rendering scheduler.",
"sig": "28071027423ba80501cf86cb5de30ed0cda47725079df4a818bb4bd30142620e3612c7e8e3e78ad3692d341f4de204722adefdb96c27524edf5c103bd8b7932c"
}