Automatic opening of Messages upon taking a screenshot

Hi all,

I have an issue that I cannot find a solution for. Upon making a screenshot (both with cmd+shift+4 and with cmd+shift+5), macOS Catalina automatically opens the Messages application and the screenshot I have just taken is in the text field, ready to send to a new contact.

I will be grateful for any help, as this issue is very annoying.

Thanks a lot in advance !