Images broken on "Settings -> Packages" on Mac due to Proxifier's loop detection feature

[jmdacruz]

This is related to #595

I'm using Proxifier (https://www.proxifier.com/) to simulate a transparent proxy on a corporate network. Proxifier has a feature called "infinite loop detection" which, when enabled, tries to detect processes that may be creating requests in an infinite loop. Apparently, the "Atom Helper" process triggers this rule when navigating to the "Settings -> Package" page, since it starts retrieving all the images for all the authors on the page.

As a result, Proxifier blocks the requests and blacklists the Atom Helper process (actually, "blacklisting" is not accurate, since what it does is creating a special rule for that process to connect directly without using the proxy). The end result is that the images are not correctly downloaded to the cache in ~/Library/Application Support/Atom/Cache, and you end up with broken images on the Atom UI.

The workaround is to disable this "infinite loop detection" feature in Proxifier, and then delete the cache and restart Atom. Everything works perfectly from that point on.

I think the bug here is that Atom (or the "Atom Helper" process) should not be caching the images if these couldn't be downloaded because of a temporal error. The cache entry should either 1) not be set at all, or 2) set with an invalidation TTL or expiration time which will allow the "Atom Helper" process to retry later