Impossible to add image class

[Mecanik]

Version(s) affected

2.6.0

Description

I tried with default attributes and also tried with attributes extensions, the class on images will not be added.

Same thing with links, classes are not added.

How to reproduce

Example:

![some image](...){: width="100" height="100" #test .image}

Output:

<img width="100" height="100" id="test" src="..." alt="some image">