Could you possible attach the testcase as attachment. "Attach new file". But in general it isn't defined how contextmenu should work with shadow DOM, since it has been removed from HTML spec, and is still in progress of being removed from Gecko too (unless other browser vendors implement it too). See https://bugzilla.mozilla.org/show_bug.cgi?id=1372276#c0 But then https://bugs.webkit.org/show_bug.cgi?id=179020 did land to webkit, but is that enabled on Safari?
Bug 1606533 Comment 1 Edit History
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Could you possible attach the testcase as attachment. "Attach new file". But in general it isn't defined how contextmenu should work with shadow DOM, since it has been removed from HTML spec, and is still in progress of being removed from Gecko too (unless other browser vendors implement it too). See https://bugzilla.mozilla.org/show_bug.cgi?id=1372276#c0 But then https://bugs.webkit.org/show_bug.cgi?id=179020 did land to webkit, but is that enabled on Safari? Though, that patch didn't add support for contextmenu.