Make desktop notifications more visible and configurable

One big problem I and many of my colleagues have with almost all chat applications and also with keybase on the desktop is that it is easy to miss that a message has arrived. For us, keybase would mainly be used on a Linux desktop computer (using various window managers, I use Mate on Ubuntu)

Currently there are only two ways to see that a message has arrived:
* the pop-up notification but this one disappears after a few seconds, so when looking at the other monitor or not looking for a few seconds it is easy to miss this
* a tiny dot inside a tiny icon in the task notification area. On a huge monitor or for people who do not constantly stare there or have less than perfect eyesight, very hard to notice.

So personally I would like something that is 1) easier to notice and 2) sticky, persisting somewhere on the screen. But I know that the tastes of people are extremely different with this.

So would it not be possible to allow this to get configured? The very old Skype had something for the Linux client where each event could get associated with not just its own sound but optionally a command to run.

I know I could probably achieve this by forking (kudos for this brilliant app being open source!!) but ...

The issue names no files, tests, or entry points. Start by locating the desktop notification implementation and its configuration surface; done would provide more noticeable, persistent notifications with configurable behavior.

Written by the indexing model from the issue text.