> any other editor than the one integrated in my IDE

Appears as you are waiting for silver bullet to be invented …

What about, say, Inkscape (SVG WYSIWYG editor)? Do you expect it to appear as integral part of your IDE? What kind of IDE it will be then?

Are you saying that it is not common to see IDEs and other editors support HTML in addition to other text-based formats?

It feels like by “people” you mean “people similar to me”, thus connecting your two statements.

I mean, I too want to use a single text editor, but I’m not sure that people generally feel the same way.

Which of these statements are likely to be true:

When developing applications with multiple different types of files (XML, HTML, JSON, Javascript, etc)

  A) They prefer to use different editors for each of type of file.
  B) They prefer to use a single editor that supports all the formats.

How about:

  A) Text editors don't typically support multiple different file formats.
  B) Text editors typically support multiple different file formats.