303998 2025-12-11 08:51:39 -0800 [SVG] Interoperability Failure: <style> inside external SVG referenced by <use> is ignored (Blink implements, WebKit/Gecko do not) 2025-12-12 02:17:41 -0800 1 1 1 Unclassified WebKit SVG WebKit Local Build PC Windows 11 RESOLVED DUPLICATE 249080 https://bugs.webkit.org/show_bug.cgi?id=249080 P2 Normal --- 1 arif.hossain.9213 webkit-unassigned karlcow sabouhallawa zimmermann oldest_to_newest 2165118 0 477694 arif.hossain.9213 2025-12-11 08:51:39 -0800 Created attachment 477694 Test files This issue reports an interoperability failure where Chrome/Blink applies styles from a <style> block within an external SVG referenced by <use>, but WebKit (Safari) and Gecko (Firefox) ignore these styles. This discrepancy breaks the intended modularity of SVGs. The Scalable Vector Graphics (SVG) 2 specification, Section 5.6.3 (Style Scoping and Inheritance), states that the stylesheet objects from the referenced external document should apply to the elements within the use-element shadow tree. WebKit's current behavior appears to contradict this intent. Steps to Reproduce: 1. Save the attached SVG file as rounded_marks.svg. (This SVG contains an internal <style> block.) 2. Save the attached HTML file as test.html. (This file uses <use href="rounded_marks.svg"></use>.) 3. Open test.html in Safari/WebKit. 4. Open test.html in Chrome/Blink (for comparison). Observed Behavior (WebKit/Safari): The SVG renders nothing, or renders unstyled elements, indicating that the stylesheet from the external document is not being applied to the shadow tree. Observed Behavior (Chrome/Blink): The SVG renders correctly, successfully applying the styles from the external <style> block, aligning with the intent of SVG 2 style scoping. Interoperability References: Gecko/Firefox Bug (Closed INVALID): Mozilla Bug 2004673 Upcoming Blink/Chromium Bug: Chromium Bug 467468919 Expected Behavior (Advocacy for Convergence): I strongly support the application of internal <style> blocks from the external SVG to the shadow root. This behavior is crucial for modularity, as it allows the SVG to be a self-contained component that defines its own styling. We request that the WebKit team review the SVG 2 specification (Section 5.6.3) and consider aligning with Chrome's implementation to enable this intended and highly useful feature for modular SVG components across the web. 2165158 1 arif.hossain.9213 2025-12-11 10:55:01 -0800 https://www.w3.org/TR/SVG2/struct.html#UseStyleInheritance 2165285 2 karlcow 2025-12-11 17:18:44 -0800 This seems a duplicate of the bug I'm trying to fix. Bug 249080 https://github.com/WebKit/WebKit/pull/53713 But is a bit more complex than I initially thought. 2165286 3 karlcow 2025-12-11 17:20:54 -0800 see my comment in the PR. Gecko is implementing the specification correctly and is receiving web compatibility pressure, because some web developers have different behaviors in different browsers. This behavior has been shipped since Firefox 56 in 2017. https://bugzilla.mozilla.org/show_bug.cgi?id=265894 Blink has just published an intent to ship to align with the behavior of Firefox and the specification. https://groups.google.com/a/chromium.org/g/blink-dev/c/8ZT9te1tP4E https://crbug.com/40663285 2165287 4 karlcow 2025-12-11 17:22:18 -0800 Hi Arif, thanks for the report. > We request that the WebKit team review the SVG 2 specification who is "We"? 2165344 5 arif.hossain.9213 2025-12-12 00:35:14 -0800 (In reply to Karl Dubost from comment #4) > Hi Arif, > thanks for the report. > > > We request that the WebKit team review the SVG 2 specification > > who is "We"? My apologies, this bug report was generated by an AI. The 'We' it mentions likely refers to the developers. My actual issue is the following: WebKit is failing to apply styles defined in an external SVG's <style> block when rendered inside a <use> shadow root. Please confirm this behavior using the attached files. 2165364 6 karlcow 2025-12-12 02:17:41 -0800 OK so let me close this as a duplicate *** This bug has been marked as a duplicate of bug 249080 *** 477694 2025-12-11 08:51:39 -0800 2025-12-11 08:51:39 -0800 Test files test.zip application/x-zip-compressed 1819 arif.hossain.9213 UEsDBBQACAAIAA22i1sAAAAAAAAAAAAAAAAJACAAdGVzdC5odG1sdXgLAAEEAAAAAAQAAAAAVVQN AAfa9TppJvY6abykNml9U7FOwzAQ3Sv1H0wGBFLdtAwIpU4WKCsMZWBCbnKNTW0nsp2UCPXfcdIU pa3hFvvunp7v3Z3J1dPL4+r9dYmYlSIZj0h7IkFVHgegAhcZj5AzwoBmyeHe+RIsRSmj2oCNg7fV M34ILvKKSoiDmsOuLLQNUFooC8rhdzyzLM6g5ingzpkgrrjlVGCTUgHxfDo74bPcCkiWX1SWAkh4 cI/VdQhjmy6EBrYusgZ9n8Zak1TnXEVotrjMMeA5sxGaz2Y18+Q/K2P5psHcgjQRSp0g0B4cFTxX uJf8B24/VNCaqXNfvRk3paBNhNaiSLe+x0wJqcWaWl640v+RJbm66aRNOoW728V5Da1hbDVVxk2k cG2aGw8hxq6LW6wqiY2kQjjYnZfrOmJFDdqny89z7xvL/qJzxysJh6MnYb+qvduuwHCRXIfPloRU BhDTsIkDXVQqg+yjrchMHTRISOjSyclrvwwk7Nndxwm7H/QDUEsHCGLZHsRsAQAAUQMAAFBLAwQU AAgACAALrotbAAAAAAAAAAAAAAAAEQAgAHJvdW5kZWRfbWFya3Muc3ZndXgLAAEEAAAAAAQAAAAA VVQNAAfH5zppAPY6aUtz4meVVlFv2zYQfi/Q/3BxXuzMih0HLTAtDuCmaxcsTYbY2dBHWqYlIhIp kFRkrxiwf7i/1CMpRpItZ6kBAzZ5vPvu7vuOvFBPMWyylKtpL9E6D0ejsixPy/NTIePRZDwej9Ci B0+Mlh/EZtobwxjeje23d/n2DcCF0tuU2p8ApxmRj0HEZJRS+ObWAEYnMJ1O4eru9tP154f72eL6 7hb+nN1fzz7c/Dq3eyejt28a5r+JEjLCt2D8KSBSFHwFOqFQ+e6v6JoUqQ7h/XhgTz+fhSCwKHiR md1funxrkqZASZTYAEA3mvKVAsZLIlfQl2TFSAoJZXGiD7h3myGcvcs3nTFKtqKNGExBXxMeU66N b9zVyQHXdi+ESYfjK5EKCWJta+GK0+kiMnYhHGMD93yYet/Mvt49LOBqdnP1cGMb0tmHhcBKgWJ/ UxNTFNITAfpIgA1+mykEgdkNlmITGn4g/DZ2kkZFSjS14E2NC+XdurZ6Y/z8RUEVSy1JpCEhaZ1w 1RVQoso/F4xr37omGBchhAjj9p+I7Nf4BjCCCQTgVhv9HNp+2u3BS+jXBRLIgC6yNZWUR9Q3ZS+T T0JmeBD7+d+/Evo5M1QgcDWfQyS4Qk7oo3YVW34r/BM4ATx6UkF2uQ12MFrZFMg4IiNIKY91Amvk S83CnyAmeQPcR/ZkaNpKCeW13ALKZ0kt1XZpFgSKxhnyOHAhWhVuYTd1bJQYXQ6NXl+sLOJzhFtS XVLKXfgG5LmnhU3IagXWUmRQoQItIKYaJM0I44zHoHKC/WkmgEG6wLfzGrQJYiMNjSp3EzDCmS++ 3lzffu4S0a2ANcPaBlAiS3i6hZIYmJis0lI84jQThU4Zx3ohdpVgF2uw5mgIXHDaDjp3R63QXf5W nkQyskyb2boYYTMVe2gIUSGxTdrOlJ2UFjU4V+EljURG1bN0n8djF0PcST/HDolshwWSGgqsiEro CnKiNZU8hLr0OHoUw9SGUHcPZV+tNgiySFBgkXXn8GoWPTqMR/sgTUAiJdmGB5pdLddBd4Df44ys uGt8eehGQ3ZwkQZR91Bi+alU/prTcDYZwjmKZAg/42BTTDMcEd2gxXqtqG7xdw/6/hj7o3LqlY4x HQjTRz/c63jR5vD8NJ4rq+3LVo34szxHAdiR72W/8ndBHVaG7TnX8FFVwMglIrm3wx7m1AP6x1tX 2nw/hi+z+9/rG87sHavMPAK+1UOhfjW0Z1ZgLetsdx4Ae/Q+YF9dybsy3LXG2cZdi7xtveJsh3vr Qzg9d5dBV/pnk670lyx+VfJoh3qd/ED69sRk7BT+qhLYE8drfE28rgzW/n+LgG/TkX+c2n8xsNW0 txQ66VXv1YujIID+R/eWNDxxpFimxE8MvAQCb1xJJkqJwudy46nbs47t2R6MLn39296xDSmRMSpN IuV/1Dmm7FybrGIb4sI8zS+/A1BLBwjAMP96PQQAAMILAABQSwECFAMUAAgACAANtotbYtkexGwB AABRAwAACQAYAAAAAAAAAAAAtoEAAAAAdGVzdC5odG1sdXgLAAEEAAAAAAQAAAAAVVQFAAHa9Tpp UEsBAhQDFAAIAAgAC66LW8Aw/3o9BAAAwgsAABEAGAAAAAAAAAAAALaBwwEAAHJvdW5kZWRfbWFy a3Muc3ZndXgLAAEEAAAAAAQAAAAAVVQFAAHH5zppUEsFBgAAAAACAAIApgAAAF8GAAAAAA==