Proposed change

Update local calendar to process calendar events in the executor. Now that local calendars can come from remote urls, they may contain huge amounts of recurring events which need to be expanded when loaded, which may slow down the network thread. Moving to an executor can stop this from blocking the event loop.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes Loading an ICS file caused a reboot loop #138439
• This PR is related to issue: Update local calendar to process calendar events in the executor #144233
• Link to documentation pull request:
• Link to developer documentation pull request:
• Link to frontend pull request:

Checklist

• The code change is tested and works locally.
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