Add a note about Snap confinement

[gammazero]

Users who want to know how to install IPFS may not be aware of Snap's confinement behavior. So, I thought it useful to add a note someplace where they might see it before they install the Ubuntu Snap package.

Hopefully, this can prevent issues like this one: ipfs/kubo#7872

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[aschmahmann]

cc @olizilla, does this sound good to you?

[olizilla]

Yes indeed! Good idea to warn about it. I would use a ::: callout or similar to highlight it, and move it to directly below the table.

[johnnymatthews]

Moved the warning into a :::warning box. Saying that, if installing things through Snap without the --classic flag is gonna cause issues, should we just advise folks to use the --classic flag all the time?

[aschmahmann]

@gammazero I'm not sure this is actually enough. Since the snap has strict in the config.yaml users get Warning: flag --classic ignored for strictly confined snap ipfs.

We should probably just change to telling people to use --classic (and changing our config.yaml). We could potentially give access to more plugs as well (perhaps, system-files).

[johnnymatthews]

Updated the instructions to use --classic by default.

changing our config.yaml - @aschmahmann

What's required for this?

[olizilla]

The snap default is strict confinement. The ipfs snap has always had strict confinement. Are lots of folks getting suprised by that? The installing user can add and get files via an ipfs daemon installed by snap, so I'm not clear on what the problem is.

Snap is not other package managers, and we should be careful around our assumptions of how things should work. We should definitely review the list plugs and add any that are missing tho. I am mildly against reducing the confinment at this point unless i am missing some context.

[johnnymatthews]

Right. In that case, I'm not sure what to do here then. Installing IPFS with Snap is easy to set up and for most folks to use, but comes with confinement complications. I'd like to keep a simple one-liner here for Ubuntu users though.

[olizilla]

The best thing would be to caveat it in the docs for now, similar to the orginal PR, and open an issue on go-ipfs to review the snap.yml config to make it as un-annoying as possible, given that snaps defaults are much stricter than other package managers.