Avast’s Android ‘Clear Clipboard’ is mostly a useless function, unless you like constant Warning notifications? ???
I got to this conclusion by using the function and testing it, obviously.
Basically what it does is copy a blank piece of text, so if you paste it pastes nothing, but when going to your Android clipboard everything is still there including a blank space…
All the things you’ve copied is still there and usable by just one click.
I would like Avast to fix this please, as it could be a wonderful feature! 
Thought that is a option in CleanUp and not AMS…
Hi, this feature in AMS cleans only the last record on Clipboard, but it notifies you whenever you copy some data, so if you use the feature regularly, there should be no problem.
I can verify that is what AMS is doing on my Galaxy S6; it is just an empty copy into the clipboard to clear it. Could be an old tactic when Android clipboards could only hold one cut/copy at a time.
Just to shed some light on this. Original Android only holds 1 record in Clipboard. Some phone manufacturers (like Samsung for example) have a clipboard history. The thing is, the history only accessible to users. Other apps can still access only the last item (whatever phone they’re on), so if you clean the clipboard from AMS, other apps can’t access what you had there.