With the power of computers constantly increasing, the user has more and more programs opened in their associated windows: why would you close windows if your computer is powerful enough to handle them? The problem is that your computer's screen is often too small, especially screens of notebooks.
4t Tray Minimizer aims at helping you to better manage your windows, allowing you to open more of them without getting overwhelmed with their number. With 4t Tray Minimizer, you can indeed minimize any window to the tray, make any window transparent, force it to stay at the top, and roll it up and down. If you don't need one of these features, you can disable one or more using options. You can also define shortcuts allowing you to quickly perform any action without needing to move your cursor. If you're willing to instantly get more space for applications you're going to open, then you can click the main window on "Minimize to tray all applications". It seems that the additional buttons aren't correctly displayed in special windows that are not following the Windows standards; it shouldn't be a great issue because there are not many and it's only an esthetical issue.
This software should completely satisfy you, because it is bundled with a great range of features. If you want even more control, you can check the paid pro version that will bring you a few extra features.