I’d say nothing that can’t be achieved by docstrings.

Is it like show formatting marks / show hidden symbols in modern software, that shows ends of paragrahs and tabs?

Sure, just as I said, this would work id you don’t need menu or fuzzy matching. But I would recommend using fzf history search anyway, it’s just too good.

Let me tell you that you can also add comments to your terminal commands and use them to search history using fzf. This might sound confusing but basically you do this:

commandwithweirdoptions --option1=value1 --option2=value2 # run the usual thing

Then you press Ctrl+R and type anything like «the thing», it uses fuzzy matching and finds the command in history, with a menu of other similar commands. Press enter, done.

Note that you need to have fzf installed, otherwise there is no fuzzy matching and no menu of matching history results.

I’m pretty sure it was a joke.

Everyone did this at some point, but nobody would admit such a silly thing happened to them.