I got the report below originally about the package that we tested for RHEL at the time, but it's basically the same as the Fedora package anyway (and the issue shows up in current releases). I could reproduce it with the current gimp-2-8 and master branches.

Basically: in SWM drag the tool options from below the toolbox to its right edge, this will resize the toolbox to only one column and the window will be resized to a greater height. This may be even more than the height of the screen, which renders the window not maximizable in e.g. GNOME Shell (can't say if other window managers show this behavior).

Fedora bug: https://bugzilla.redhat.com/show_bug.cgi?id=1031106

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Description Martin Simon 2013-02-28 08:06:52 EST

Description of problem:
The Gimp 2.8 has a new feature to attach the toolbar into several columns. When I attached Tool option panel (in default under the Toolbox) to the right side of the Toolbox (the toolbox and tool options are now horizontally, not vertically as before), the toolbox shrinks into one column of tool icons and expand horizontally behind the monitor borders. It's especially annoying in single window mode, when in does not permit the fullsreen mode.

Version-Release number of selected component (if applicable):
gimp-2.8.2-6.el7.x86_64

How reproducible:
100%

Steps to Reproduce:
1. Start gimp
2. Enable single-window mode (Windows -> Single-Window mode)
3. Drag&drop the Tool options (by default under the Toolbox) from its original position right side of the Toolbox
4. Try to maximize of F11 to fullscreen

Actual results:
The Toolbox shrinks and you are unable to resize the gimp vertically. The fullscreen does not work at all and behaves weird

Expected results:
The gimp should now the maximal height of the monitor and if the shrunk toolbox does fit the height, it should expand a bit to the width.

Additional info:

Comment 1 Nils Philippsen 2013-11-15 10:43:32 EST

The reason for this is that moving the tool options dockable to the right "squeezes" the toolbox so it's only one column wide, but very tall (too tall for most displays), which results in e.g. GNOME Shell refusing to "maximize" the window, i.e. fit it into the current display, which it can't because the window is already taller than the display.

Here's a workaround: After step 3, there's a handle to the right side of the tool options dockable. Drag it to the right, creating some space for the toolbar so it can use additional columns. Then you should be able to reduce the window height, or maximize it.

I'll clone this for Fedora, and raise this with upstream -- I'm not familiar with the UI layout code and can't estimate how much effort it would be to fix this.
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