Gimp-Forum.net

I cannot find this  under the image menu bar?  I am running GIMP 2.10.20 (revision 1),

Help appreciated 

The GIMP user interface is now available in two modes:

multi-window mode,

single window mode.

When you open GIMP for the first time, it opens in single-window mode by default. You can enable multi-window mode unchecking Windows → >Single-Window Mode) option in the image menu bar. After quitting GIMP, GIMP will start in the mode you have selected next time.

By default, Gimp will save the last settings before closing.

In multi-window mode the position of the windows is important when switching back to single window mode. If you do not like what you see use Edit -> Preferences -> Window Management then click on Reset Saved Window Positions to Default Values. That gives the single window arrangement same as a new install.

If you want Gimp to retain any particular Window arrangement, either single or multi-window:

Set Gimp Docks up exactly the way you want to start a new session.
Then Edit -> Preferences -> Window Management
Untick Save window positions on exit
Click on Save Window positions Now.