[CopyQ 8.0.0] Theme not applied preferences window and resizing issue in preferences/tab menu

[gituser823]

Describe the bug
The theme is not applied to preferences, commands and Search windows. And probably other Menu I did not test.

Also in the preferences window the sidebar for "Tabs" can not be properly resized.

To Reproduce
Steps to reproduce the behavior:
Open preferences.
Go to "Tabs".
Resize the middle bar.

Expected behavior
The middle bar should be resized so that it stops and resizes to wherever I release mouse1.

Screenshots
Heres a gif of the issue:

Version, OS and Environment
(Get details from copyq version command if possible.)

• Application Version

• 8.0.0

• OS

• Linux Mint Debian Edition 6

• Desktop environment, window manager

• Cinnamon 6.0.4