This is likely dumb question, but I need to be sure. Situation where you download the installer/downloaded file, extract app file from it, eject disk image form desktop, then put downloaded file into trash and it suddenly don't want to be deleted. I suspect system was still using it in some ways... though disk image had been ejected. App itself seems to work, opens and does what it was meant to do. Just slight worry if there might be internal error causing security issues. Is this possible? Or if App actually works, then it works 100%? I've had it happen few times with different apps and was never sure if I should go and remove them and re-install, eve if they seemingly work. Will Thunderbird get less secure? Will Malwarebytes not detect everything? Thoughts like that. Just don't know how apps works - are they like one big bundle that either works or won't work at all and as long as they seem to work, they are 100% fine?