LGTM2 On Mon, May 13, 2024 at 4:36 PM Mike Taylor <miketa...@chromium.org> wrote:
> Hi Morten - > > Appreciate the response. I spent some time looking at > https://github.com/search?q=%22instanceof+CSSGroupingRule%22+language%3AJavaScript&type=code&l=JavaScript > as well as "instanceof CSSRule" earlier, but didn't see anything > immediately worrying (granted, it's hard to predict perfectly how the > tooling-related scripts might handle sites in the wild that might ship the > problematic patterns). > > LGTM1 to ship. > On 5/9/24 6:16 AM, Morten Stenshorne wrote: > > On Wed, 8 May 2024 at 17:18, Mike Taylor <miketa...@chromium.org> wrote: > >> On 5/8/24 3:37 AM, Morten Stenshorne wrote: >> >> Interoperability and Compatibility >> >> Low risk. The one possible issue is if an author uses "instanceof >> CSSGroupingRule" or "instanceof CSSRule" with a page rule object and makes >> incorrect assumptions based on that. However, given that this is already >> shipping in Firefox (and also that in Firefox, even CSSStyleRule inherits >> from CSSGroupingRule, as the spec says - whereas Blink still doesn't), the >> risk should be very low. >> >> I agree the risk is likely very low, or contained to just a few >> sites/applications - have you done any investigation to try to find any >> problematic code examples that you mention (via GitHub search or >> HTTPArchive)? >> > > There's a use counter - > https://chromestatus.com/metrics/feature/timeline/popularity/4862 - for > CSSPageRule, but I'm not sure how useful it is, since it will count as long > as someone e.g. iterates over the rules in a style sheet and there happens > to be an @page rule in there. The use is currently at 0.07, but the number > isn't that useful, apart from being an absolute worst-case number. > > Here's a constructed problematic case if CSSPageRule suddenly inherits > from CSSGroupingRule: > > ``` > <style> > @media screen { > div { > color: hotpink; > } > } > @page { > margin: 1in; > @top-center { > content: "Header"; > } > } > </style> > <script> > for (const rule of document.styleSheets[0].cssRules) { > if (rule instanceof CSSGroupingRule) { > // Aha! You're a media rule! (d'oh!) > // ... > } > } > </script> > ``` > > How likely is that, though? > > >> *Gecko*: Shipped/Shipping ( >> https://bugzilla.mozilla.org/show_bug.cgi?id=1868215) >> >> Noting that the patch should ship to Firefox release channel (126) in >> about a week, per https://whattrainisitnow.com/calendar/. >> > > Ah, right. Pretty recent change. > > On that note, earlier (some time in 2023), Firefox changed CSSStyleRule to > inherit from CSSGroupingRule - > https://github.com/w3c/csswg-drafts/issues/8940#issuecomment-1747351690 > That sounds like a much riskyisher change, but allegedly it went just fine. > >> >> *WebKit*: No signal >> >> Can we request a signal? Or do we have any other indications about their >> intentions here? >> > > Done. https://github.com/WebKit/standards-positions/issues/346 > > -- > You received this message because you are subscribed to the Google Groups > "blink-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to blink-dev+unsubscr...@chromium.org. > To view this discussion on the web visit > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/ee67bf7d-78f9-4309-b831-00942ae69936%40chromium.org > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/ee67bf7d-78f9-4309-b831-00942ae69936%40chromium.org?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "blink-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to blink-dev+unsubscr...@chromium.org. To view this discussion on the web visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAOMQ%2Bw-mNDO7Z2A0-KaB5tz4WAaDfp1%2B5WFpqCNrdaZZLZbPzA%40mail.gmail.com.
