I'm distributing a Safari Web Extension iOS app via TestFlight (built from a Chrome MV3 extension via xcrun safari-web-extension-converter on Xcode 26.0.1). The extension installs and registers correctly, but its popup never opens when the toolbar item is tapped. The behavior is silent — no error, no flash of UI, no console output. The Safari ᴀA menu just closes and the user is back at the article. WHAT WORKS: Extension appears in Settings → Safari → Extensions, can be enabled Permissions can be granted (Always Allow on Every Website) Extension appears as expected in Safari's ᴀA address-bar menu WHAT DOESN'T WORK: Tapping the extension item in the AA menu produces no popup, no error, no visible response of any kind. Same on iPhone and iPad, both on iOS 26. WHAT I'VE VERIFIED VIA IPA INSPECTION: Extension .appex contains: manifest.json, popup.html, popup.js, background.js, content.js, and images/ with all icons _CodeSignature/CodeResources files2 lists 11 entries — every web extension resource is sign