Example with a normal space:
The quick brown fox jumps over — and, sometimes, under — the lazy dog.
Example with a thin space:
The quick brown fox jumps over — and, sometimes, under — the lazy dog.
This Smashing Magazine article discusses spaces in more detail. At the bottom of the article is a list of different spaces and their corresponding HTML entities:
This is because hackernews has font-family: Verdana, Geneva, sans-serif and I have neither of the named fonts installed.
On my system, hackernews is rendered using Dejavu Sans. This is presumably a default for Firefox on linux which I never realised until today.
I'm using the default Verdana font. Here's a screenshot of what the post looks like on my computer (Firefox on Windows).
I guess I should have added a disclaimer to say that the thin space may not always appear correctly depending on the browser/platform/setup etc. :-)
¹ https://www.flickr.com/photos/mwichary/albums/page1
² https://www.google.com/doodles/30th-anniversary-of-pac-man