Initial values when start plotting

[isSerge]

When start plotting initial values:

• plotted and remaining are NaN
• Syncing 0 of null blocks
  

[isSerge]

This happens when a local node is not connected to the network (for example no Internet connection).
In this case system.syncState returns:

{
  currentBlock: 0
  highestBlock: null
  startingBlock: 0
}

which results in NaN value for plotted and remaining.

@rg3l3dr I guess we should implement UI that will let users know there is a connection problem

[isSerge]

This also happens when you're running Subspace Desktop as a single node