tststs
alt-O is now "toggle outline view"
With the release of 1.21.0 beta, and the (now officially supported) atom-ide-ui package, The alt-O key combination is being used for the 'toggle outline view' action. You may want to change the default, or at least define a secondary key combo. You might also consider querying the user on installation about which alt-O action they prefer.
Atom needs a standard way to present these conflicts to the user and resolve them, but if they've released one I don't know about it.
A little late to the party :D
It seems that facebook stopped working on atom-ide-ui. Do packages transition to some alternatives or is atom-ide-ui being forked by the community?
My assumption has been that it will continue to be developed by the community, or perhaps that Github will take it over. So far I don't see evidence of that. The perils of being too dependent on a single corporation?
Aha! Take a look at https://discuss.atom.io/t/impact-of-nuclide-extension-being-removed/61242/11