It's perfectly reasonable to expect a text editor to support more than literal unicode, and to work with a variety of commonly-used formats.
It's perfectly reasonable to expect a text editor to support more than literal unicode, and to work with a variety of commonly-used formats.
The blog post states that the contents of said "text file" were quite literally <!DOCTYPE HTML><html><head></head><body>
This is not a mere text file. At all. This is a HTML document that might be deemed valid by a very permissive validator.
Just because HTML might be stored in a text file that does not mean that a noncompliant HTML file ceases to be a HTML file.
One might, possibly, still argue about the text encoding of a .txt file (I’m old enough to remember Unicode being a new fancy alternative to ASCII), but that’s about it.
[0] Sometimes I reminisce about the good old days of classic Mac OS, with resource forks and separate file type metadata: https://en.wikipedia.org/wiki/Resource_fork
That statement is quite wrong and shows a good dose of ignorance. To start off in UNIX systems the extension means nothing regarding whether a file is an executable or not. All it takes is a +x flag and a file format (header, magic number) that can be executed.
Also, file extensions mean nothing. In fact, a popular and very basic trick to fool clueless users to run malware (and one which any anti-malware tool checks) is to sneak executables with a different extension, because it only means something to clueless users.
And a file with a txt file extensions means nothing at all. The only thing that matters is the file content and it's file permissions.