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Joined 3 years ago
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Cake day: May 19th, 2021

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  • Yeah, the four color problem becomes obvious to the brain if you try to place five territories on a plane (or a sphere) that are all adjacent to each other.

    I think one of the earliest attempts at the 4 color problem proved exactly that (that C5 graph cannot be planar). Search engines are failing me in finding the source on this though.

    But any way, that result is not sufficient to proof the 4-color theorem. A graph doesn’t need to have a C5 subgraph to make it impossible to 4-color. Think of two C4 graphs. Choose one vertex from each- call them A and B. Connect A and B together. Now make a new vertex called C and connect C to every vertex except A and B. The result should be a C5-free graph that cannot be 4-colored.











  • wisha@lemmy.mltoLinux@lemmy.ml*Permanently Deleted*
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    5 months ago

    We could take this further and let developers specify exactly the dependencies they need! No more bloated runtimes! App A could specify libfoo>=1.23.45 while app B specify libfoo<1.24 and Flatpak could resolve the compatible version automatically!

    Serious answer: If space saving is the goal, traditional packaging is the way to go. Allowing multiple runtimes is a slippery slope away from the core idea of Flatpak (simplest dependency management possible so developers don’t have to test many configurations).

    (Not that there’s anything wrong with traditional packaging with more complicated dependency management - it’s just not Flatpak’s thing).











  • Flatpak apps cannot set their own permissions “on installation”. If flatpak tells you some weather app uses only the network permission then that is all the app is going to get.

    For an app to be able to change its own permissions, it first needs permission to the flatpak overrides directory. Any app that does this gets an “Unsafe” designation in gnome-software.

    Also about most apps requiring filesystem access to work: I have 41 flatpak apps on my system (Silverblue so everything is flatpak). Only 6 have access to my home or Documents directory. (11 apps requested full filesystem or homedir permission, but 5 of these work perfectly fine after I turned off their permissions in Flatseal).

    Notably, “large attack surface” apps like Thunderbird or Firefox don’t have access to my Documents. File uploads and email attachments go through the file picker portals.