Window binding likely is Sushi’s second most primary feature because it integrates well with the multi-panels, the most primary feature. It similarly is present in only one other browser, Tungsten, where it is known as app capturing.
Window binding is the binding of an application to one of Sushi’s windows or panels. To bind a window, first, have Sushi next to the app of interest. If the app is in the background, then alt-tabbing, clicking the taskbar, etc. will cancel the binding process. Click the Bind Selected Window option in the settings menu, and select the app. The app should instantly occupy the space of the applicable panel or window. Moving Sushi’s window will cause the bound app to follow it with little delay.
There are a few limitations with the functionality.
Firstly, the binding can break temporarily and cause the bound window to disappear generally behind Sushi’s frame at least on Windows. This is a more common occurrence when the app is bound to one of Sushi’s panels rather than an actual window, but it does happen with windows, nonetheless. When this happens, there are a couple ways to quickly fix this on Windows: press the Windows key (and quickly tap it again to deactivate the Start Menu) or navigate to the app through alt-tabbing or the taskbar. Panels basically are frames that occupy windows and are the result of tab splitting. They can be thought as window panes that have most but not all of a proper window’s functionality are useful for dynamically resizing content. If you want to bind two apps and have them sized so that one occupies 70% of the screen and the other occupies 30%, then you can bind them both to two panels that a part of the same window, resize them, and then use the Panels to Windows setting (under Window SubMenu in 0.14.5+). Doing this will make the binding inherently more stable because the apps are being bound to separate windows.
Secondly, it’s not as compatible as you would expect with the always on top feature because it makes the bound app more likely to be hidden behind the panel or window.
Window binding definitely does have its advantages.
As long as you recognize the limitations, it really is good for productivity. The app is bound not just to a panel or a window but to an individual tab, as well. This means you can open other tabs and even bind other apps to them. Move the panel or window around, and all of the content will follow. Even if you don’t keep the app bound, you can use the feature to just resize the window to the needed width and close the window to stop the binding.
Window binding is more than just something to be used once out of curiosity and then to be forgotten in many cases. Productivity is a notable example. For instance, you can bind Notepad++ in one, smaller panel while viewing a tutorial in the second, larger panel. It’s even more effective when being able to use one monitor for tasks. While I use Sushi primarily for the multi-panels, window binding makes it even more difficult to primarily use other browsers.