I think you are comparing two different things here. Axios is a library while Fetch is a native function on modern browsers. It will always be performant to use native functions but a library will always be easier to use due to its abstractions. I think it would be better if you will be comparing Axios vs another library that abstracts HTTP Calls, or comparing Fetch vs XHTTP. Good story though.

Saifur Rahman Mohsin notice when i mentioned "when working with other developers".

Don't be shy to ask from the owners on where to start and areas that might be affected by the desired changes. Contributing to Open-Source is also a great way of improving yourself by learning from others. Cheers to contributing! From there - little by little you will surely be able to work your way in completing the task. And, add a tad more confidence. You are doing great! This Chrome Extension is a must for any developer - and they are Open-Source too (which I contribute as well). Guess what? They are using Vue!

Good stuff. Though be wary of amending commits (message) when working with other developers. It rewrites the commit which would result as different on those who already pulled it.