I know I have been down this road before.
Ok, so I should know. But with what I know, this isn't fitting with what is happening.
I am trying to change the icon from the default to the one which looks like a radar. (track_changes)
But when I type in the name and deploy I lose most of the dashboards.
All the buttons come up as unassigned.
Sorry I don't really want to do it just now as it is painful getting it back to working.
But that aside, I'm wondering why it is the name I put in isn't working and/or causing the problem.