Looks like a standalone app as opposed to a web library, unless I misread.
In any case, we don't typically offer compatibility with X markdown editor or whatnot for a variety of reasons:
Markdown can be disabled in favour of other parsing languages (like BBCode, etc)
There needs to be support for post-related functions offered by the existing composer, such as topic images, file uploads, tags support, etc.
The short of it is, it takes quite a bit of work to ensure compatibility and full functionality, which is why at current we only support default and redactor.
To just the author and mods, unfortunately we cannot support this yet, as we don't have a "post author" pseudo-group. That is a good idea, though.
We did accomplish this via nodebb-plugin-support-forum, you could try this and see if it still works?
I installed nodebb-plugin-header-extend plugin and then wanted to go back to default navigation.
After going back to default navigation, I was able to see some small blank icons in the navigation , so I activated the plugin again and deleted all the icons.
Then all the icons were gone, and I was not able to put back any navigation icons into it. Is there anyway to make it default? like resetting just the navigation part?