How do I know for sure they are free in the sense that I can use them in a book cover, broadcast television, print magazines? My advice is, always modify the icons a little yourself.
The codebase example is worryingly common though, I have had countless colleagues try and modify a piece of code they found and include it in their PRs without adhering to the license.
>> It is important to note that if the icon is a standard symbol or image that is commonly used in a particular industry or field, it may be difficult to claim copyright protection. Additionally, if the icon is a functional element, such as an icon that is necessary for the operation of a software program, it may not be eligible for copyright protection.
That's what all the coding AI are supposedly for.