Having delete Mailspring.app but today I found it is still in Mail.app

Hi, guys

I remember I deleted it a couple of months ago. But it is still in the list of default email client in my Apple Mail app. In addition, it is working with email links and even asks me to copy its files to /Applications folder.

I tried to manually locate the orphan program but there is nothing on my disk. Therefore, I came here for help: How should I remove it completely? Thank you.