[browser] All restored tabs are loaded at startup

[Olivier Tilloy]

When restoring a previous browsing session, a new tab is restored for each previously open tab, and a webview is instantly instantiated and loaded. With a large number of open tabs, this probably makes the startup time of the application longer, consumes more memory right away, and if on mobile data consumes more MBs too.

Only the webview for the first tab should be instantiated at first, other tabs should be empty placeholders which trigger the instantiation of the corresponding webview on demand.

This means we’re going to need to save and restore the title for each open tab (we’re currently saving and restoring only the current URL).

[Oliver Grawert (ogra)]

currently there is also one location popup request per tab ... i wondered why i get multiple ones for a day every time i opened a fresh browser page ... until i noticed that over the day all external links i had clicked in any open webapps resulted in a tab being kept open in the background ... consuming resources (often with embedded videos etc)

i think it would be helpful if:

a) we had the number of open tabs somewhere visible in the top bar (i could imagine just having a number left or right of the burger menu, though indeed i'm no designer :) )

b) the location request would be shown only once for the app and not per-tab (i heard there is work going on to use the trust store which will fix this)

[Olivier Tilloy (osomon)]

Added an ubuntu-ux task to get design input on the request to have the number of open tabs visible somewhere in the UI.

[Giorgio Venturi (giorgio-venturi-deactivatedaccount)]

We are not planning to have the number of open tabs in the top bar, there is not enough real estate.
People in the future will be able to access the tabs by simply executing the bottom edge swipe.

Re: restoring sessions, I agree with Olivier - the best approach is to load the page only when the tab is tapped