Are all Magisk Modules Open Source? I noticed the main place to download modules is here

https://github.com/Magisk-Modules-Repo

some in the links section link the source which just loops back to the same page. So are all the modules hosted on github itself open source? as i see what looks like the contents of each module there.

I suppose some modules might be posted on XDA that aren't on github and i know not all Xposed modules on Xda or repo.xposed.info aren't open source.

Appreciate all help.
Github does not equal open source. Because a Magisk module is on Github it does not mean it is open source

You can have both open and closed projects hosted on Github and Magisk is no exception as you can see from this XDA post by Magisk developer (though instructions pertaining to Magisk are outdated)

There are projects hosted on Github with a portion of the code which is closed source and is offered as paid or pro version, for example code of
FairEmail is available on Github but the pro version features are not open source. Though I am not aware of any such Magisk module with pro component

Though this SO question is old, it gives pointers to better understand