296702 2025-07-30 08:45:13 -0700 browser.scripting.executeScript() does not inject scripts into about:blank and about:srcdoc frames 2025-07-30 08:46:55 -0700 1 1 1 Unclassified WebKit WebKit Extensions Safari 18 All All NEW InRadar P2 Normal --- 1 am webkit-unassigned am timothy webkit-bug-importer oldest_to_newest 2133408 0 am 2025-07-30 08:45:13 -0700 ## Description browser.scripting.executeScript does not inject scripts into about:blank and about:srcdoc frames. It returns "Failed to execute script. Extension does not have access to this frame." even though content script is allowed to run in these frames. ## Steps to reproduce Create a test extension to reproduce this issue. Manifest: ``` { ... "background": { "scripts": [ "background.js" ], "type": "module" }, "content_scripts": [ { "js": [ "content.js" ], "matches": [ "<all_urls>" ], "run_at": "document_start", "all_frames": true, "match_about_blank": true, "match_origin_as_fallback": true } ], ... "permissions": [ "<all_urls>", ..., "scripting" ] } ``` Content script: ``` browser.runtime.sendMessage({}); ``` Background page: ``` browser.runtime.onMessage.addListener(async (request, sender) => { const tabId = sender.tab?.id ?? 0; const frameId = sender.frameId ?? 0; const result = await browser.scripting.executeScript({ target: { tabId: tabId, frameIds: [frameId] }, func: (id) => { console.log(`injected into ${id}!`) }, args: [frameId], world: 'MAIN', injectImmediately: true, }); console.log(result); }) ``` Install it and open the test page: https://testcases.agrd.dev/Filters/extended-css-rules/extended-css-iframejs-injection/extended-css-iframejs-injection Open Dev tools and look for "injected into ${id}" messages in the console. ## Expected result Four messages (one for the main frame, three for iframes). ## Actual result Two messages (one for the main frame, one for an iframe with URL). If you inspect the background page, you'll see that they failed due to "Failed to execute script. Extension does not have access to this frame.". 2133409 1 webkit-bug-importer 2025-07-30 08:45:23 -0700 <rdar://problem/157118726>