Kiview gives the user the ability to quickly preview different file types without the need to launch the default application.

.txt,.sh,.pdf,.doc,.docx,.odt,.ods,.xlsx,.xls,.csv,.odp,.ppt,.pptx,.png,.jpg,.jpeg,.kra,.svgz,.svg,.mp4,.mp3,.webm,.webp,.zip,.gz,.xz,.rar

https://flathub.org/apps/io.github.nyre221.kiview
From the terminal: flatpak install io.github.nyre221.kiview

wget -O kiview.deb $(curl -s https://api.github.com/repos/Nyre221/Kiview/releases/latest | grep browser_download_url | cut -d '"' -f 4)
sudo dpkg -i ./kiview.deb
rm ./kiview.deb

sudo zypper ar -f https://download.opensuse.org/repositories/home:/nyre21/openSUSE_Tumbleweed/home:nyre21.repo
sudo zypper install kiview

To use it you need to set a keyboard shortcut via plasma settings and invoke it while a dolphin window is active.
Any key combination is fine to activate the shortcut and it is only necessary to enter this command in the appropriate section: kiview --shortcut or flatpak run io.github.nyre221.kiview --shortcut (for the flatpak version).

https://www.pling.com/p/2148462/

1. Open the dolphin settings menu (configure -> configure dolphin)
2. Go to "Context Menu"
3. Click on "Download New Services"
4. In the search bar write "Kiview"

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