QuickLook in macOS is a great tool, for showing a quick preview of many different file types. But there are also many file types, where QuickLook doesn't offer a preview. But you can extend the supported file types by installing plugins for these file types. Here I collected a list of the most useful plugins for QuickLook. You will find installation instructions on their GitHub-Page.
To make QuickLook Plugins to work in macOS Catalina you have to execute this command in the command line:
xattr -cr ~/Library/QuickLook/xxx.qlgenerator
(xxx is the name of the plugin)
After you installed a new QuickLook Plugin, you have to refresh QuickLook with this command:
qlmanage -r
Usefull QuickLook Plugins:
QuicklookStephen
QLStephen is a QuickLook plugin that lets you view text files (f.e. README, CHANGELOG etc.) without their own dedicated QuickLook plugin
QLMarkdown
QLMarkdown is a QuickLook plugin that renders Markdown files.
QuickLook Video
Nativly QuickLook and Spotlight can handle only MPEG-Video files.
QuickLook Video adds support for other codecs like .asf, .avi, .flv, .mkv, .rm, .webm, .wmf etc.
You know even more useful QuickLook Plugins? Please, let me know!