Does Xcode's formatting still support doxygen comments

It does. The only issue I've found is with multi-line member comments in the following format.

shared_ptr MyInt; /**< This is a member comment. */

There are lots of problems with Doxygen comments. Besides Doxygen I think the whole highlighting (besides reserved keywords) and indentation is broken in Xcode 11. In one evening I have submitted eight bug reports. There are a lot more but I just stopped reporting, it is hopeless (rant off).

BTW: I did not report this one but this is also broken:

double value; ///< This is a value (look at the fading!)

I tested and it works (XCode 11).

/**

Some text which may be very long and wraps on 2 lines if needed

*/

I have to write it just before the func or var declaration.

Effectively, you can have only a single line of text (no line feed in the comment), but a very long text will wrap automatically on several lines.

Are you responding to my example? Your example does not have anything to do with what I wrote.

double value; ///< This is a value (look at the fading!)

If I put the code as shown above into a C++ file (header file with ending .hpp) only "///" is faded, the '<' is not faded. This looks really strange and does not make much sense.

I just commented on "Does Xcode's formatting still support doxygen comments"

Are you responding to my example? Your example does not have anything to do with what I wrote.

And also tried to answer to your question (tested on XCode 11 / Swift code):

/// after the declaration does not work

But

/**< This is a value (look at the fading!) */

Works

In addition:

///< This is a value (look at the fading!)

Fading works according to the XCode preferences.

Text Editing

select Fade doc comments markup delimiters

Have you checked those preferences ?

Yes, otherwise I would not see any fading.