Qlik Sense February 2019: Automatically saving does not always work.
Starting from Qlik Sense February 2019 the Save button has been removed from the script editor.
The script editor now saves after every keystroke, so, saving manually is, generally, not necessary. The photo below says that the script has been saved. But when I close the app, it sometimes happens that my new piece of script is not saved.
I used Firefox and I saw this article. But also when I use Chrome, I have the same problem.