Improve Experience of Adding Event to iCalendar

[anna-yeddi]

Steps to reproduce

1. Go to any page that has calendar events, for instance: https://loudoun.libnet.info/events
2. Choose any event and activate it
3. Locate to and activate "Add to calendar" control
4. (On the Libnet website, step 3 would open a menu with different options) activate "iCalendar" option
5. Process with the flow and observe the behavior

Expected behavior

1. IOS own screen with Add event view is opened.
2. Adding to calendar closing this view and returns a user back to the event page they just interacted with

Actual behavior

1. There is one interim screen that opens before the iOS dialog with "Add to calendar?" Notification
2. There are two interim screens after the event is added: one webview of addtocalendar.com - user has to press "Done" to dismiss it - and the other one is an empty tab in Firefox that is indefinitely loading. That tab has to be manually closed by a user to get back to the initial event tab

Note: Safari has no interim steps and is working as expected. Also, Firefox iOS sometimes fails to actually save the events in calendar (but I haven't saved specific websites for it yet, so not flagging this in the general behavior description)

Device & build information

• Device: iPhone 15 Pro, iOS version 18.3.1
• Build version: Firefox 135.2 (51018)
• First seen version: ? A while now

Notes

Attachments:
Pre-iOS calendar event view:

Post:

Pressing Done >

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