Foreign characters stopped working when inserting signatures with OnNewMessageCompose event

[SimonDania]

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Foreign characters stopped working in the Outlook 365 client when inserting signatures with OnNewMessageCompose event. It appears the issue is only present in the current channel. If I roll back to the monthly channel, it still works as expected.

Your Environment

• Platform [PC desktop, Mac, iOS, Office on the web]: PC desktop
• Host [Excel, Word, PowerPoint, etc.]: Outlook 365 (Client)
• Office version number: 2312
• Operating System: Windows 10/11
• Browser (if using Office on the web): N/A

Expected behavior

The foreign characters "Æ", "Ø" and "Å" are expected to be shown correctly.

Current behavior

I open a new mail and the OnNewMessageCompose event is fired as expected. Afterwards my signature is inserted, but I get weird characters instead of the expected letters. If I fire the same event manually, the foreign characters are shown correctly.

Steps to reproduce

1. Open Outlook Client
2. Start a new mail
3. When the signature is inserted through our add-in, the characters are broken.

Context

The issue has been present ever since the current channel was updated in january.

Useful logs

• [ ] Console errors
• [X] Screenshots
• [ ] Test file (if only happens on a particular file)

How it looks:

How it is supposed to look:

[kinkoazc]

This is a duplicate of https://github.com/OfficeDev/office-js/issues/3892.

[SimonDania]

This is a duplicate of #3892.