[hibbelig]

This is going down a rabbit hole. “This” is an English quote, whereas „this“ is a German quote; note that the open quote character in the English quote is equal to the close quote character in the German quote.

Then there is a less-often used style of quoting, similar to the French style, but: «this» is the French quote, whereas »this« is the German version. Yes, the open and close quotes are swapped.

I applaud the idea, but just want to point out that there are dragons lurking in the shadows.

[ygra]

All of “”" parse the same as ", so bracketing doesn't really enter into it. This is just to prevent smart quotes from destroying code, not to have more levels of nesting.

[pgcj_poster]

Additionally note that «this» is mostly used in French online and in Switzerland, while « this » is more common in professionally typeset works in France. Those are U+202F NARROW NO-BREAK SPACEs between the guillemets.

[seszett]

Don't forget that the French quotes should have (non-breaking) spaces inside « like this » - only when used with the French language though, other languages usually don't use such spaces.