Cannot edit first occurrence of recurrent event without changing entire series

[MartinSfromB]

Steps to reproduce

1. Create a weekly recurrent event
2. try do edit this
3. you can only update entire series

Expected behavior

The buttons "Update entire series", "Update this an future occurrences" and "Update this occurrence" should be available.
Maybe you created a series and the first occurrence must be cancelled. For historic reasons of course you need the entry. Maybe In description you want to write down the reason for the cancelation. ... But you cannot do this to cancel the whole series.

Actual behavior

The buttons "Update entire series", "Update this an future occurrences" and "Update this occurrence" are not available. Only "Update entire series".

Calendar app version

6.6.1

CalDAV-clients used

No response

Browser

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Client operating system

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Server operating system

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Web server

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Database engine version

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PHP engine version

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Nextcloud version

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Updated from an older installed version or fresh install

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List of activated apps

Nextcloud configuration

Web server error log

Log file

Browser log

Additional info

No response