Slack When Ready troch Inbox When Ready

Like with Inbox When Ready, my personal trigger for making this is because I'm frustrated by going onto Slack to check on a single thread, or get a particular bit of info, and then getting totally derailed by all those bright red dots.

What the extension does:
1. When you open Slack, you'll always see your personal direct messages channel, instead of whatever channel you had open previously.
2. All your Slack channels will be hidden by default.
3. Your notification dots will display as gray instead of red.

This is the alpha version of this extension. For more information, see here:
https://docs.google.com/document/d/1zzxWB3OWG3dXwIelf8oEtJL1yVGhPLZEXz2iy6s57Nc/edit#