Changes in Preferences->Interface->Keyboard causes that Commands-Bar disappears
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#### Summary:
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Changing keyboard-issues in Preferences cause that Commands-bar disappears, which thereafter can't be restored.
#### Steps to reproduce:
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Let's assume, you start inkscape as it would be for the first time.
(delete preferences.xml in "..AppData/Roaming/Inkscape.." first).
Enter "Preferences->Interface->Keyboard". Click on "reset" or change some Shortcut.
#### What happened?
Commands-Bar disappears
#### What should have happened?
Commands-Bar is still there
#### Sample attachments:
First "preferences.xml" after starting Inkscape for first time:
[First_preferences.xml](/uploads/de40c71f4740b9807cc1ea2b83000d46/First_preferences.xml)
"preferences.xml" after error occurred:
[With_Error_preferences.xml](/uploads/8681454ec8ca8c48d1ed360613cd0d98/With_Error_preferences.xml)
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#### Version Info:
- Inkscape Version:
Inkscape 1.1 (c68e22c387, 2021-05-23)
GLib version: 2.68.2
GTK version: 3.24.29
glibmm version: 2.66.0
gtkmm version: 3.24.3
libxml2 version: 2.9.12
libxslt version: 1.1.34
Cairo version: 1.17.4
Pango version: 1.48.5
HarfBuzz version: 2.8.1
Poppler version: 20.12.1
- Operating System: Win10Home
- Operating System version:64bit, 21H1 Build 19043.1023
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issue