[Time to Visualize] popup notification when leaving an unsaved dashboard

[AlonaNadler]

After the big change expected to happen with by value and by reference in the dashboard.
It would be easier to accidentally lose work done on a dashboard.

For example:

• users creates a new dashboard
• created 5 new panels (by value)
• clicked twice on the dashboard app to open another dashboard

All the work on the new dashboard is not saved anywhere and disappear. In the past, the panels would have been saved in visualize. With the new behavior (which is better in most cases) it will be easier to lose work done on the dashboard.

It be good to either have an autosave mechanism or a popup before leaving an unsaved dashboard.

Another option is to have a save before you leave popup

there might be more options but I think losing something you worked on is very bad experience, and we need to think of ways to help users avoid that

@majagrubic @stacey-gammon @ThomThomson @timroes

[elasticmachine]

Pinging @elastic/kibana-app (Team:KibanaApp)

[stacey-gammon]

This would also solve the problem with drilldowns where you click on your drilldown to test it out and you lose the edits you just made.

Now that I think about it though, I'm surprised the drilldown configuration isn't preserved when going back to dashboard because it should be stored in local storage. 🤔

[AlonaNadler]

After discussing with the team, a popup will appear when users leave the unsaved dashboard.

cc: @timroes

[timroes]

Related to the discussion in #35812

[ThomThomson]

This was fixed in #86939