I edit directly in Winrar (version 3.93 or earlier).
Just open xxxx.zip, double-click on the file you want to edit, and if the file type is not associated with any application, I set it to always open with notepad.
When editing and saving the file (straight from inside the zip), Winrar informs that the file has been modified and I want to save the zip.
There, everything is fine, without needing to extract and compact again.

On Android, the Flashlight + Clock file manager app also lets you edit directly in the zip. And NextGen recognizes the edited file.