This is the most basic feature you can expect from a script editor - if it does not tell you what line you are on currently, and does not let you click "Go to line...", then you are severely limiting yourself. Back in my early programming days I used Notepad all the time, and back then it had no "Go to line..." feature - I literally had to press the Down cursor key however many hundred times to get to the error line, as long as I hadn't lost count along the way.
Line numbering will help you find your bugs quicker - there is no two ways about it. Do not settle for an editor that does not have line numbering.
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