

If anything, it being on Github makes it impossible for them to claim ignorance about the license. If they scrape your code off your site, they’d have to actively add checks to look for the license.
They’d rather just use the “it’s probably as fine as every other piece of HTML” assumption they’re working with now.
I use Nextcloud, but as you said it’s a bit big, and with each update it’s slowly turning into more of the entire G-Suite.
I’ve used filebrowser, but be aware that until just a few days ago, it gave out access to a shell. Even with that turned off, I’d be very weary of allowing access from out of the VPN. I had a server pwned with filebrowser appearing to be the vector, and to my memory console access was disabled for the account most likely breached.