Default email issue

I recently switched from Thunderbird to eM Client as my default email program, I had had both on my system for a while and decided to switch back to eM Client. However there is one issue I have not been able to find a resolution for. I have gone through and reset my default app preferences in Settings (Windows 11) but when I try to send a Libre Office document as an email it still opens Thunderbird. I believe the problem has to do with the MAILTO setting. Here’s a screenshot of what I’m seeing.
Settings

Hopefully you can provide an answer.

It is not the mailto protocol.

Please look in the Windows Registry what is set for HKEY_LOCAL_MACHINE\SOFTWARE\Clients\Mail

If it says Thunderbird, change it to eM Client.

So:

It actually says Microsoft Outlook, which I don’t have on my machine. Should I change that?

I also looked at another registry key, HKEY_CLASSES_ROOT\mailto\shell\open\command. The value there is @="“C:\Program Files (x86)\Mozilla Thunderbird\thunderbird.exe” -osint -compose “%1"”. Could that also have a possible impact?

Change the option I mentioned to eM Client.

Thanks Gary, that did the trick. I appreciate your quick responses.