Discord does markdown differently than intended: it’s better for non-techies because hitting enter once is more intuitive than the alternative, but the standard way to insert line breaks in markdown is to type two spaces at the end of the line you want to break.
It’s not about the amount of swap space, it’s a problem that happens when swapping happens for big chunks of data at a time.
Windows aggressively swaps out things way before it’s necessary, you can try increasing the system’s “swappiness”; I’m writing this from my phone, but when I get to my PC I’ll write out how to do it (unless somebody else does it before I do).
You can set it by writing vm.swappiness=60 in a file like /etc/sysctl.d/50-swappiness.conf.
The value 60 is arbitrary, if you increase it the system will try to swap out things more aggressively; the name of the file is also partially arbitrary, but AFAIK, it has to begin with two digits — the system will read all the files inside /etc/sysctl.d in order, and the settings in higher-numbered files will be applied over lower ones.
Officially, this is the explaination of the vm.swappiness parameter.
You can read and write the value with your shell:
#!/usr/bin/bash
sysctl vm.swappiness # shows you the current value
sudo sysctl vm.swappiness=69 # sets the swappiness to 69 AND shows you the new value
Spaces behave like this because markdown was designed to be like HTML but quicker to write and easier to read without formatting;
most web services that use markdown translate it to HTML rather than parsing it directly, and in HTML whitespaces are supposed to work like you demonstrated in your comment.
The reason for this behavior in HTML is “because someone in the 90s said so”, I’m afraid.