Scenario: You're working in a restored session with unselected, restored tabs. These tabs haven't loaded their content yet, because we deferred loading as a perf optimization. When we first select such a [pending] tab, the docShell is restored to its old state, showing an old, stale state. There are already bugs on file that actively discuss whether this behavior is valid, but this bug is about something different: It does not help that we're showing the loading indicator when we're restoring a tab to its former state. The indicator seems to inform us that we're fetching fresh content from the Web, but in fact we're just resetting to an older version. Very confusing. Let's fix that to at least _not_ show a loading indicator in this case. Showing a local, older copy shouldn't take long enough to show a spinner for anyways.

(In reply to Mike de Boer [:mikedeboer] from comment #0) > When we first select such a [pending] tab, the docShell is restored to its > old state, showing an old, stale state. Except when it isn't... Full page loads seem to be fairly common for me. Any change here will need to take this into account.

(In reply to Mike de Boer [:mikedeboer] from comment #0) > > It does not help that we're showing the loading indicator when we're > restoring a tab to its former state. The indicator seems to inform us that > we're fetching fresh content from the Web, but in fact we're just resetting > to an older version. Very confusing. > > Let's fix that to at least _not_ show a loading indicator in this case. > Showing a local, older copy shouldn't take long enough to show a spinner for > anyways. To be absolutely clear here, what you're talking about is the tab throbber, and not the tab switch spinner, correct?

Yeah, the blue one that's recently been switched to use CSS anims.