Removing leftover Avira Antivirus files

Some time ago I removed the free version of Avira Antivirus from my MacBook Air which is running Big Sur. Although the process that was described for removing Avira Antivirus should was supposed to remove all Avira files, it seemed that there were still some files leftover.

I tried to use the command file that Avira has posted on the web page headed "How do I uninstall leftover files relating to Avira Antivirus for Mac without the uninstaller". My initial attempt to unpack the command file failed and I wasn't sure why. However, today I spent some time looking into what the problem was and managed to unpack the file Avira_Uninstaller.zip and, by following the instructions provided on the Avira website, have the file run. From the messages that it produced it seemed the the leftover files had all been removed. However, when I went did a search on Library/ I found many files remaining including some Avira Javascript files.

Why is it that the command file that Avira provides to remove leftover files doesn't seem to do that?  

What do I do to completely remove the leftover files?