User story 1.

• Enter Dashboard X. You see some nice graphs.
• Zoom in into some range on some graph to see data closer
• Exit Zabbix, go home
• On the next day open Dashboard X. Observe that all graphs are loaded in the time interval that you zoom in last time(like 1 hour yesterday) and not something more actual like 'last day, last week etc'
  

What to do:

• I suggest adding an option to define the default time interval for the dashboard in Edit mode
• If you zoom in or change time interval - params specifying the range must be added to the URL of the dashboard.
• If you are reentering the dashboard without any params defined in the URL - it must be shown with the default time interval defined by the dashboard owner. Useful default would 'Last day', 'Last week', 'Last 1h' etc.
• If you are just refreshing the page or sending someone a direct link to the dashboard - time interval is preserved, thanks to HTTP params in the URL.