How to detach modal dialogs from main window? Popup dialogs attached to window title and not movable

I found a much easier solution. Actually you can configure it with the GNOME Tweaks (previously known as "GNOME Tweak Tool"):

Just disable "Attached modal dialogs" under "Windows".

Just for those that was unable to solve this, here is what I did to make my dialogs moveable.

I used dconf-editor which can be easily installed by: sudo apt-get install dconf-editor

1. Open: dconf-editor
2. Browse to: org -> gnome -> shell -> overrides -> attach-modal-dialogs
3. Set it to: false

Or everything in one line without installing dconf-editor:

1. Detach dialog: dconf write /org/gnome/shell/overrides/attach-modal-dialogs false
2. Attach dialog: dconf write /org/gnome/shell/overrides/attach-modal-dialogs true

Using Ubuntu 12.04 BTW.

For GNOME Shell

You can disable it in gnome-shell with a single command in the terminal. Open it with Ctrl + Alt + T shortcut and use the command below:

gsettings set org.gnome.mutter attach-modal-dialogs false

You will get rid of that popup attachment.

On older versions of GNOME Shell was under org.gnome.shell.overrides, probably since this issue.

For Cinnamon

To disable the same on cinnamon, you need this command

gconftool-2 --set --type=bool /desktop/cinnamon/windows/attach_modal_dialogs false

You can use gconf-editor to do the same thing. Install it with sudo apt-get install gconf-editor command.

The "design decision" is based on how macOS does it. It solves the problems with modal dialogs popping up without seeing to which program they belong to. The dialog should provide enough information to make your choice.

However, at least for gnome-shell you can change this behavior with

gsettings set org.gnome.mutter attach-modal-dialogs false

This is by design in Cinnamon, as well as in gnome shell

This feature is for arranging Modal Dialogs within their parent window, and can be disabled gnome shell by the use of gconftool. It can also be disabled in cinnamon.

This feature has also been seen in Mac OSX

This worked for me on Gnome 3.30.2 to allow detaching dialogs:

gsettings set org.gnome.mutter attach-modal-dialogs false

or to re-attach them:

gsettings set org.gnome.mutter attach-modal-dialogs true

and, to get the current setting:

gsettings get org.gnome.mutter attach-modal-dialogs

On my Ubuntu 12.04 with Cinnamon, I used the gconf-editor method, but the path was org -> cinnamon -> overrides -> attach-modal-dialogs

Cinnamon 4.8.4:

Cinnamon settings > Windows > Tab Behavior > Groupbox Window focus > Attach dialog windows…

I found a link with a way to fix this, this method is outdated in newer releases and gsettings should be used instead.

In GNOME 3 the default modal dialog behavior is to attach the window so both the back and front window will be firmly attached together and dragging one of them will move even the other window, like if they became a single window.

This behavior can be changed to restore the old way the modal dialogs were treated in the previous GNOME releases. To detach the modal dialogs from the main window you will just need to execute the following command (in a single line) inside a terminal window:

gconftool-2 --set /desktop/gnome/shell/windows/attach_modal_dialogs false --type bool

To attach the modal dialogs to the parent window you could execute:

gconftool-2 --set /desktop/gnome/shell/windows/attach_modal_dialogs true --type bool

After issuing one of the previous commands you'll need to restart the GNOME Shell by logout the current session