How to Shift+Enter as default into confluence editor

[Marcus Tang]

look like confluence doesn't appear to be a way to change the settings of line spacing defaults.
why NOT ??? JUST DO IT !!!!
confluence assume every enterprise staff are all html editor ???
confluence hope normal person understand enter=<p> but shift+enter=<br> ???
I DON'T UNDERSTAND !!!!!

[Stephen Wrathall]

I wonder if there's an opportunity here to make the difference between <shift>+<enter> and just plain <enter>. I only recently learned that the former does a simple newline, and the latter starts a whole new paragraph. 

Now that I know the difference, I absolutely love it! But it took me a long time to figure it out - I wish it was clearer.
(Writing this last sentence with <shift>+<enter> to show the difference, even though it ideally deserves a whole new paragraph).

[Nic Brough -Adaptavist-]

Confluence is supposed to be a simple editor and a clean reading experience.  If you are thinking of messing with line spacing, you are moving away from a standardised clean reading experience, and hence Confluence is probably the wrong tool - you need a formatting-centred tool rather than an easy reader.