There’s no one answer to this. You, the user, need to see the licenses of the various tools you are using to see what they allow—including JS libraries etc. If it comes from Fedora, it should follow a “good license” and you should be OK:
There’s also a difference between having stuff installed on your laptop and actually using it in a commercial project. For example, you can have vlc installed on your system for personal use, but that doesn’t mean you’re using it to build your commercial website. If you are working for a firm though, you should check with them to make sure you follow whatever their rules/guidelines are.
Now, if a package is in RPM Fusion, it’s because something stopped it from being included in Fedora. So, let’s go through what the page says to see how software in RPM Fusion is categorised:
Free repository
Software that uses a free license, but is not accepted in Fedora for various reasons.
Example: video players…
Enable by installing rpmfusion-free-release package.
These are usually tools that require additional software to function (codecs for example), which are not FOSS. Fedora only includes tools that can function without requiring other repositories. So if a media player requires software from RPM Fusion to work, it won’t be included in Fedora, it’ll be included in RPM Fusion Free. This does not mean that the media player is not FOSS.
Nonfree repository
Software that uses a nonfree license, but is otherwise redistributable.
Example: Nvidia binary drivers
Enable by installing rpmfusion-nonfree-release package.Until the creation of the tainted repositories, the redistributable status was only analysed with respect to copyrights holders and not rights related to (software) reverse engineering for inter-operability purposes. The “tainted” repositories were added to fill this usage.
As it says, these are not licensed with FOSS licenses but are freely redistributable.
Free Tainted
Software that use a free license, but may have usage restriction in some countries.
Example: libdvdcss
Enable by installing rpmfusion-free-release-tainted package.
If you are using tools from here, you need to see what the laws in your country are.
Nonfree Tainted
Software that uses a nonfree license and which is not explicitly redistributable, but is allowed for inter-operability purposes in some countries.
Example: b43-firmware, nouveau-firmware, dvb-firmware.
Enable by installing rpmfusion-nonfree-release-tainted package.
Same here. Check what the laws in your country are.
We can’t give you legal advice here for obvious reasons (the first being that most of us are not lawyers XD). So you’ll have to check it up yourself and make up your mind. I do hope the answers here help though.
This is a great website to learn about licenses: