Is it okay to use this plugin after haven’t been tested for 2 years?

The plugin page indicated it was last updated 2 years ago so it appears it may have been abandoned. But when I tested using it on my website, it still works like a charm. I’ve read articles many times that it’s not advisable to use this kind of outdated plugin for it creates safety risk. Since I only know how to use the plugin but nothing beyond that, I’m just wondering if it is a good idea to still use it? This plugin really works great with my website and I can’t find any other alternative that is as “to the point” as this one. Can anyone please offer me some insight? Thank you very much.