Opacity slider in Preferences->Appereance is not intuitive.

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It is not intuitive because when guake is using ARGB, it works in a way that by adding opacity it makes the terminal more transparent which is not very logical.

The better solution would be to move the slider below the color chooser and rename it to "Alpha", "Alpha channel", "Transparency", "Color transparency" or something like that. Then it will manage the transparency of the color. By adding more transparency to the color it will reveal more of the background image if we have selected some image, or it will reveal more of the things that are below terminal if we don't have background image selected.

[SnapShot]

A patch which renames opacity option to transparency, moves it under the color option and adjusts the code to the behaviour that adding transparency means revealing more of the background image or the content under the terminal.

I tried to do minimal modification to .glade file by manually modifying the position and the name of the slider with text editor instead of using Glade.