Bewertet mit 3 von 5 Sternen
This extension works reasonably well, though it could work better with unloaded tabs. By default, Firefox doesn't load background tabs when a session is opened, and only loads them when you click the tab, which can be good performance-wise if you keep a lot of tabs open. With this extension's default settings, it forces these tabs to load as soon as they're moused-over, in order to generate a preview, which kind of defeats the purpose of having them remain unloaded to begin with. Move the mouse across the tab bar to go from one tab to another, and you suddenly have a bunch of tabs loading between the two.
The extension does provide an option to not autoload these tabs, but this makes it much less useful. Instead of a preview, you're presented with a blank white square for unloaded tabs, which is not particularly useful when hunting for a tab in a large session.
It would be nice if the extension provided the option to use cached thumbnails of these pages. Firefox actually does store such thumbnails in PNG format for its tab grouping feature, though I don't know if they're accessible to extensions. If they are, that would likely be a good way to handle it. Even if they aren't, it seems like the extension might be able to manage its own cache of tab thumbnails.
At the very least, I'd like to see an option to add a delay between previewing tabs. Currently, you can select a delay to wait before showing the first preview, but after that, adjacent tabs are previewed as soon as your mouse moves over them, until the preview popup is closed, resetting the timer. If the timer could be reset when moving from tab to tab, a preview would only appear once you stop the mouse pointer over one, avoiding the issue of loading all tabs in between.