`chrome.sidePanel` undefined errors for Opera

[twschiller]

Describe the bug

• There are some chrome.sidePanel errors that seem to be associated with users on Opera
• We don't officially support Opera - users will see an "Unsupported Browser" banner
• No enterprise customers are on Opera
• Opera might not implement the sidePanel API yet / have its own version of the sidePanel API: https://help.opera.com/en/extensions/sidebar-action-manual/
• https://app.datadoghq.com/error-tracking?query=&fromUser=true&issueId=f1c3e542-4e83-11ef-a820-da7ad0900002&refresh_mode=sliding&source=all&from_ts=1727877602767&to_ts=1728482402767&live=true
• https://app.datadoghq.com/error-tracking?query=&fromUser=true&issueId=b6f1b610-1da0-11ef-b6ae-da7ad0900002&refresh_mode=sliding&source=all&from_ts=1727877602767&to_ts=1728482402767&live=true

To Reproduce

Steps to reproduce the behavior:

1. Install the extension in Opera
2. Click the toolbar icon

Discussion

• If sidePanel API is not available, should we throw as a BusinessError that the browser does not support the side panel?

Desktop (please complete the following information):

• Browser: Opera