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ajQueue is (as far as I can tell) the best queue plugin out there. It was made because I wasn't satisfied with the existing queue plugins, all of them either being massively overpriced, or lacking basic features
As long as you don't break anything, i'll probably accept any merge requests you submit. I like to have the least number of steps possible for server owners updating my plugin.
If you need any help making your changes, feel free to contact me on discord. The invite link is on the plugin page ;)