How to enable dragging windows with alt-click in gnome 3 / gnome shell
You can also use gnome-tweak-tool to change the key back to Alt. The option is called Modifier to use for modified window click actions or Window Action Key (in 3.10 and later versions) and is available under the Windows category. See http://www.ryanlerch.org/blog/alt-click-drag-to-move-windows-no-longer-works-in-fedora-18-gnome-3-8/. Enable it as follows:
- Open a terminal.
- Type:
gnome-tweak-tool - Click Windows.
- Set Window Action Key to:
Alt - Close the tool.
Alt+Drag now works.
For Gnome 3, a command-line solution that may be used in scripts:
gsettings set org.gnome.desktop.wm.preferences mouse-button-modifier '<Alt>'
I have also used this feature regularly in Gnome on Fedora, and was disappointed or frustrated that it seemed to have disappeared as of Fedora 18. All is not lost, it's just moved one key over!
What used to be Alt+drag is now Super+drag. Super is the Windows/Apple/Meta key next to the Alt key on most keyboards. In the process of finding that, I also discovered that Super+middle button+drag resizes windows (which apparently used to work with Alt too, but I never knew about it).
This did what I needed:
gconftool-2 --set /apps/metacity/general/mouse_button_modifier --type string "<Alt>"
I figured it out based on another question: Gnome3 - Change window drag shortcut
It seems that alt-click-drag is usually enabled and I found several questions wanting to disable it. My case was the opposite. The feature was disabled, and I really wanted to enable it.
UPDATE
This solution worked for Gnome 3.0 in 2012 June, and it no longer works today. See the other answer I linked above, the answer seems to have updated more recently, or @STW's comment below.