Inconsistent Behavior with Teams Deep Link Across Access Methods

The issue with your Microsoft Teams deep link not working when manually opened in a new browser tab is likely due to missing authentication or session context. When a user clicks the link directly (e.g., from an email or within Teams), their current session and cookies are preserved, allowing the deep link to resolve correctly. However, manually pasting the link into a new tab often lacks that context, leading to unexpected behavior or failure to load.

To avoid this, use the official Teams deep link format (https://teams.microsoft.com/l/entity/...) which is more reliable across access methods. Ensure users are signed into Teams before using the link, and whenever possible, encourage them to click the link rather than copy/paste it. If your app uses tabs or custom pages, make sure it handles Teams initialization and context retrieval via the Microsoft Teams JavaScript SDK (microsoftTeams.initialize() and getContext()). For a more advanced solution, consider redirecting users through an intermediate page that checks for a valid Teams session before opening the deep link.

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