I saw that several years ago someone started work on a portable app for Line but as far as I can see they stopped development and it was abandoned. Line is a fantastic app for communication. If someone could help to make this app portable I think it would make a great addition to Portable apps. I would definitely recommend it to others and use it myself.
You might also reach out to the Line folks specifically and ask them if they can create a portable distribution. At least for basic portability, all you need is them to put all files and settings in the same subfolder (not saved to AppData or elsewhere). It won't update along with your other PortableApps files, but it will behave portably.
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