CalDAV Calendar time zone offset question

I use the CalDAV platform to access a calendar. Unfortunaltely, the times shown in my lovelace frontend show all entrieg with a 1 hour offset (I tried the custom version too).

calendar_entry

My other caldav clients on Thunderbird, iOS and Android display the right time 10:00 to 12:00

caldav_thunderbird

My timezone ist set to Europe/Berlin. The inquiry into time zone settings delivers the expected result:

{{ utcnow() }}
{{ now() }}
{{ utcnow().astimezone() }}
{{ now().astimezone() }}
{{ utcnow().tzinfo }}
{{ now().tzinfo }}
{{ now().astimezone().tzinfo }}

2022-01-22 10:29:00.010731+00:00
2022-01-22 11:29:00.010820+01:00
2022-01-22 11:29:00.010878+01:00
2022-01-22 11:29:00.011066+01:00
UTC
Europe/Berlin
CET

I checked the forums without success. Any advice appreciated.

Solved: Problem was a Firefox browser setting: privacy.resistFingerprinting was set to true. After turning it off, everything was OK. ResistFingerprinting tweaks the browser timezone, which in turn is used to render content. The problem applied to history_graph as well.