so as Kagami said: Safari on iPhone is not also supported yet on the beta. If you bypass with a UA string override and detect any bugs which should not be because the feature is already supported on Firefox, please let me know. I'm happy to route any bugs inside Apple. If there is a bug in Firefox such as Bug 1909933, feel free to cc me on the bug. Webcompat united. :)
Bug 1909801 Comment 6 Edit History
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so as Kagami said: Safari on iPhone is also not yet supported on the beta. If you bypass with a UA string override and detect any bugs which should not be because the feature is already supported on Firefox, please let me know. I'm happy to route any bugs inside Apple. If there is a bug in Firefox such as Bug 1909933, feel free to cc me on the bug. Webcompat united. :)