Legacy System Extension ?

In the short term, what is the best thing to do about this Warning (?) 'contact the developer'... or just ignore it ? and what happens when the OS is updated ? My tech knowledge is very limited, I do not know what 'Malwarebytes Corporation' is, or does, nor do I remember ever consciously installing whatever it is... and I find the Apple Support answer rather vague. I am looking for a simple answer, and if that is Delete, how to do that? To my innocent non-techie mind- Malwarebytes Corporation, sounds rather sinister...