Re-factor props/syncable functionality.
(This is a
The parent-child relationships between DisplayContexts, Displays, and DisplayOpts is continuing to be a cause of bugs and kludgy workarounds.
Both parent and child instances register listeners on themselves, but parent instances are really only necessary for property value synchronisation.
syncable module should be re-written (or a new module written) which just proivides synchronisation capability. A solution similar to the
fsl.fsleyes.group module might work.
Another thing ... I would like to be able to run
FSLeyes (or parts thereof) without having to create a hierarchy of DisplayContexts (and associated classes).