Despite it being one of the most popular and feature rich download managers out there and it being foss, it seems that most repos don't have it ( except for flahub iirc) Is there is any reason behind that?
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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if that's the case then that's explains it
but its a bit misleading to call it FOSS tbh
They might mean free as in beer, instead of freedom. It's the plugins that aren't open source, altough they are required to be useful.