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issues.

Describe the bug
After updating to the latest version 6.0.0~focal using Linux Mint I noticed that my keyboard shortcut to show/hide the main window doesn't work anymore. It's not just the combination, but any shortcut I enter there doesn't trigger anything.

To Reproduce
Steps to reproduce the behavior:

1. Change a shortcut in the preferences and save it
2. Try to invoke the shortcut

Expected behavior
In the case where you set the shortcut for "Show/hide main window" it won't show or hide the main window

Screenshots
N/A

Version, OS and Environment

$ copyq version
CopyQ Clipboard Manager 6.0.0~focal
Qt: 5.12.8
KNotifications: 5.68.0
Compiler: GCC
Arch: x86_64-little_endian-lp64
OS: Linux Mint 20.2

cat /etc/os-release
NAME="Linux Mint"
VERSION="20.2 (Uma)"
ID=linuxmint
ID_LIKE=ubuntu
PRETTY_NAME="Linux Mint 20.2"
VERSION_ID="20.2"
HOME_URL="https://www.linuxmint.com/"
SUPPORT_URL="https://forums.linuxmint.com/"
BUG_REPORT_URL="http://linuxmint-troubleshooting-guide.readthedocs.io/en/latest/"
PRIVACY_POLICY_URL="https://www.linuxmint.com/"
VERSION_CODENAME=uma
UBUNTU_CODENAME=focal