Hi all! Thanks for posting this discussion. My name is Tai, and I'm an engineer at Webflow. Just wanted to comment that this change triggered a regression in our Designer editor.
Our application architecture involves rendering the design editor within an iframe and surrounding it with tools in the main document, some of which overlay the iframe to facilitate direct on-canvas manipulation. A feature affected by this update is our Grid overlay tool, which allows users to drag and drop elements into different grid cells directly on the canvas. Previously, our users could start a mousedown event within the iframe (e.g. selecting an element to move) and drag it to an overlay in the main document (e.g. our Grid overlay), where the mouseenter event on the overlay would fire, allowing them to drop the element into a new grid cell. After the update, the mouseenter event on the overlay no longer fires when the mouse event starts within the Iframe. This prevents the grid overlay feature from recognizing elements being dragged into it, which breaks the drag-and-drop experience. Users can no longer effectively place elements into specific cells of the grid, limiting the usability of our design tool. I've attached a simple html file that outlines this issue that you can test on version 121 vs the latest We're not sure how to handle this issue in this case, and I'm sure we're not the only apps that have a similar architecture and workflow. Can you help guide us towards a solution to address this spec-compliant change? Thank you, Tai On Tuesday, January 9, 2024 at 12:40:32 PM UTC-8 Mustaq Ahmed wrote: > Contact emailsmus...@chromium.org, fla...@chromium.org > > SpecificationNone > > Summary > > Make mouse event targets agnostic to mousedown event cancellation when the > pointer is dragged out of an iframe. When the mouse is dragged out of an > iframe, all browsers (including Chrome) send mousemove and mouseup events > to the iframe. However, if the mousedown event is cancelled, Chrome today > maintains an old WebKit exception that mousemove and mouseup events are > sent to the outer frame. WebKit removed this exception last year, and > Mozilla never showed this behavior in recent years. This feature will > remove the Chrome-only exception for this special case. > > > Blink componentBlink>Input > <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink%3EInput> > > TAG reviewNone > > TAG review statusNot applicable > > Risks > > > Interoperability and Compatibility > > This change will make Chrome fully interoperable with Firefox and Safari. > We don't expect many compat problems from this change as this is a desktop > focused special case in which Chrome is different from other browsers. I.e. > we would expect users to see the issues in other browsers already. The > compat risk is non-zero, however it is difficult to measure whether the > change to the frame target changes would be breaking without exposing the > change. > > > *Gecko*: Shipped/Shipping > > *WebKit*: Shipped/Shipping (https://bugs.webkit.org/show_bug.cgi?id=262691 > ) > > *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? > > None > > > Debuggability > > None > > > Will this feature be supported on all six Blink platforms (Windows, Mac, > Linux, ChromeOS, Android, and Android WebView)?Yes > > Is this feature fully tested by web-platform-tests > <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md> > ?Yes > > > https://wpt.fyi/results/uievents/mouse/cancel-mousedown-in-subframe.html?label=experimental&label=master&aligned > > > Flag name on chrome://flagsNone > > Finch feature nameMouseDragFromIframeOnCancelledMouseDown > > Requires code in //chrome?False > > Tracking bughttps://crbug.com/269917 > > Sample links > > https://mustaqahmed.github.io/web/interop/cancel-mousedown-in-iframe-top.html > https://codepen.io/mustaqahmed/full/yLjBraJ > > Estimated milestones > Shipping on desktop 122 > Shipping on Android 122 > Shipping on WebView 122 > > Anticipated spec changes > > Open questions about a feature may be a source of future web compat or > interop issues. Please list open issues (e.g. links to known github issues > in the project for the feature specification) whose resolution may > introduce web compat/interop risk (e.g., changing to naming or structure of > the API in a non-backward-compatible way). > None > > Link to entry on the Chrome Platform Status > https://chromestatus.com/feature/5083240891416576 > > 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. 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/61591a88-1ce1-4d8d-830a-e9390069bbc1n%40chromium.org.Document
Mouse down and hold here, and then hover over RED Target
GREEN Target (background should change to yellow on mouseenter)
