Your conclusion above is correct. Apologies for not replying earlier. I assumed we were already on the same page. :)
On Tue, Jul 12, 2022 at 4:41 AM Arthur Hemery <[email protected]> wrote: > Hey Khushal, > Just a friendly ping on that since I see you've sent the I2S already. > Cheers, > Arthur > > On Mon, Jul 4, 2022 at 2:56 PM Arthur Hemery <[email protected]> wrote: > >> Thanks for the reply! >> Let me rephrase to see if my understanding is correct: >> "To handle elements generated by shared element transition (images - >> replaced elements), CSS overflow needs to be extended to replaced elements >> that are usually not supported. Since iframes, embed, etc. are also >> replaced elements, they need to be explicitly excluded from the extension. >> This has been spec'd already". >> >> If that's the case then it's all good, sorry for the trouble :) >> Cheers, >> Arthur >> >> On Wed, Jun 29, 2022 at 5:33 PM Khushal Sagar <[email protected]> >> wrote: >> >>> >>> >>> On Wed, Jun 29, 2022 at 11:24 AM Arthur Hemery <[email protected]> >>> wrote: >>> >>>> >>>> Hi! >>>> I've run through this as a security reviewer, and my understanding is >>>> that previous discussions led to this issue >>>> <https://github.com/w3c/csswg-drafts/issues/7143> being filed, to >>>> restrict iframe overflow. >>>> I see this is in the CSS working group so is this restriction planned >>>> for all embedded content in general and not only shared elements? Also has >>>> this been spec'd yet or was there any progress? >>>> >>> >>> The restriction is planned for all embedded content. This change >>> <https://github.com/tabatkins/html/commit/16943c6e9231a4f5fab89c65ae7ddbe49f40f01b#:~:text=iframe%2C%20object%2C%20embed,%7D%3C/code%3E%3C/pre%3E> >>> includes >>> the UA CSS to enforce the restriction and has the specific elements that it >>> will be applied to (iframe, object, embed). There is no such restriction on >>> shared elements in the context of Shared Element Transitions >>> <https://github.com/WICG/shared-element-transitions/blob/main/explainer.md> >>> or >>> the new pseudo elements introduced for that feature. >>> >>> This has been spec'd. The specific edits are in these 2 changes: define >>> overflow on replaced elements >>> <https://github.com/w3c/csswg-drafts/commit/a679cd100dcf479af23b33b033bbe4c959d78258> >>> and >>> new UA CSS >>> <https://github.com/tabatkins/html/commit/16943c6e9231a4f5fab89c65ae7ddbe49f40f01b> >>> . >>> >>> >>>> The rest looked fine, thanks! >>>> Arthur >>>> On Friday, June 24, 2022 at 10:45:44 PM UTC+2 [email protected] >>>> wrote: >>>> >>>>> Contact [email protected], [email protected] >>>>> >>>>> Explainer >>>>> https://github.com/WICG/shared-element-transitions/blob/main/overflow-on-replaced-elements.md >>>>> https://github.com/w3c/csswg-drafts/issues/7058 >>>>> >>>>> Specification >>>>> https://drafts.csswg.org/css-overflow/#overflow-properties >>>>> >>>>> Summary >>>>> >>>>> This change allows developers to use the existing `overflow` property >>>>> with replaced elements that paint outside the content-box. Paired with >>>>> `object-view-box` this can be used to create an image with a custom glow >>>>> or >>>>> shadow applied, with proper ink-overflow behavior like a CSS shadow would >>>>> have. >>>>> >>>>> >>>>> Blink componentBlink>CSS >>>>> <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink%3ECSS> >>>>> >>>>> Motivation >>>>> >>>>> This change allows developers to use the existing `overflow` property >>>>> with replaced elements that paint outside the content-box. Paired with >>>>> `object-view-box` this can be used to create an image with a custom glow >>>>> or >>>>> shadow applied, with proper ink-overflow behavior like a CSS shadow would >>>>> have. Note that the svg spec already respects this property and shared >>>>> element transitions introduces a replaced element which also needs this >>>>> functionality. One of the motivations of this feature is to apply this >>>>> property and related properties (like `overflow-clip-margin`) consistently >>>>> to all replaced elements. >>>>> >>>>> Note: This is a follow up to this previous intent >>>>> <https://groups.google.com/a/chromium.org/g/blink-dev/c/0ynSPqb-k04/m/CEoVHLREAAAJ> >>>>> to >>>>> support the same functionality. The proposal has been updated based on >>>>> feedback. >>>>> >>>>> Initial public proposalhttps://github.com/w3c/csswg-drafts/issues/7144 >>>>> >>>>> TAG reviewhttps://github.com/w3ctag/design-reviews/issues/750 >>>>> >>>>> TAG review statusPending >>>>> >>>>> Risks >>>>> >>>>> Interoperability and Compatibility >>>>> >>>>> This feature changes the behaviour of the existing overflow property >>>>> on replaced elements (img, video, canvas). Currently `overflow:visible` in >>>>> a developer stylesheet on such elements is ignored during paint and the >>>>> content is clipped to the element's content-box. With this feature, >>>>> `overflow:visible` will result in content outside the element's >>>>> content-box >>>>> to paint as ink overflow. We've collected use counter data to measure the >>>>> number of sites which could be affected by this. The use counter data >>>>> collected over 1 week of a stable release (M102) is as follows. We >>>>> collected 2 different counters explained below. * The first measures any >>>>> instance where overflow is explicitly set from developer styles to >>>>> visible. >>>>> The percentage of page loads with this is 2.16%. * The second measures the >>>>> above instances but only includes the cases with object-fit set to cover >>>>> or >>>>> none or object-position set to any value other than the default (50% 50%). >>>>> The rationale behind this counter is to exclude cases which can not cause >>>>> overflow (such as object-fit:contain), even if overflow is set to visible. >>>>> The percentage of page loads with this is 0.017%. >>>>> >>>>> >>>>> *Gecko*: No signal ( >>>>> https://github.com/mozilla/standards-positions/issues/659) >>>>> >>>>> *WebKit*: No signal ( >>>>> https://lists.webkit.org/pipermail/webkit-dev/2022-June/032317.html) >>>>> >>>>> *Web developers*: No signals >>>>> >>>>> *Other signals*: >>>>> >>>>> WebView application risks >>>>> >>>>> Does this intent deprecate or change behavior of existing APIs, such >>>>> that it has potentially high risk for Android WebView-based applications? >>>>> >>>>> >>>>> >>>>> Debuggability >>>>> >>>>> This is a CSS property which can be debugged in the devtools style >>>>> panel similar to other CSS properties. >>>>> >>>>> >>>>> Is this feature fully tested by web-platform-tests >>>>> <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md> >>>>> ?Yes >>>>> >>>>> Flag nameCSSOverflowForReplacedElements >>>>> >>>>> Requires code in //chrome?False >>>>> >>>>> Tracking bug >>>>> https://bugs.chromium.org/p/chromium/issues/detail?id=1321217 >>>>> >>>>> Estimated milestones >>>>> >>>>> No milestones specified >>>>> >>>>> >>>>> Link to entry on the Chrome Platform Status >>>>> https://chromestatus.com/feature/5137515594383360 >>>>> >>>>> This intent message was generated by Chrome Platform Status >>>>> <https://chromestatus.com/>. >>>>> >>>> -- You received this message because you are subscribed to the Google Groups "blink-dev" group. 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