same............. and OPs code is not some unreadable single line monolith, it's very elegant even.
I've learned something about regex though, thx op

had the same question and only reason I look into comment section right away. Thanks for asking and the reply.
For me it is not clearly.

What is elegant about the solution in your opinion?

Thanks a lot McBurd for your reply and effort! That actually does help and is a great in depth ressource to start with. Awesome! :)

Since you do not do anything with variable afterwards (besides returning it), there is no need to assign the result to a variable.

Brackets are character classes. They match any single character between them--specific meta characters are interpretted differently. They allow ranges such as a-z for matching the english alphabet (lowercase), for example. They also support negation by placing ^ as the first character, ie, match anything BUT the following. You might want to play around here: https://regexr.com/

So there isn't actaully a term that I know of that one could search for this specific type of assignment, however, I did find this article, which I hope helps you.

https://mariusschulz.com/blog/the-and-and-or-operators-in-javascript

does filter method assume to filter out false if no filtering condition is given?

Same! I dont see that syntax too often and I dont fully understand this.
Do you know how this syntax is called or how to look that up?

This is very very clever and clean.
I like this solution a lot

the double equal sign "==" is against JS idioms and should only
be used when actually needed.
Generally === and !== is best practice

The problem is see in this solution is that it needs to interate twice over the array.

But if height was a negative number and bigger than window, multiplying it by bounce would cause an infinite loop. I think.

This solution looks very clear and excellent to me!
May I ask: Do the square brackets prevent any content from being interpreted as Regex escape chars?

h <= 0 is not needed due to instructions