To make it work in 8.2 (apart from creating routes.php file) you need to remove a line from apps/files_comments/appinfo/app.php that contains
that should be second line of code, third line of file. Then it works, but due to new side panel for file data the box is hidden, so you need to change CSS as well, in file apps/files_comments/css/comments.css change lines as indicated
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