I am using Spring Tools Suite 4 (based on Eclipse IDE).
Spring Tool Suite 4
Version: 4.8.0.RELEASE
Build Id: 202009151856
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All rights reserved. Visit https://spring.io/tools
This product includes software developed by the
Eclipse Foundation https://www.eclipse.org
This product includes software developed by the
Apache Software Foundation https://www.apache.org
Why Alt+Shift+Q, O not work?
I press 3 keys at same time: Alt, Shift, Q. Then I keep key Alt and Shift, move finger from Q to O.
Press Alt+Shift+Q and then release everything, a small window appears at the bottom right of the main window with the list of views that can be shown using this key sequence - now press O for the outline.