The problem that markdown files cannot be previewed in Idea
1. The Markdown plugin in Idea is not enabled
In this case, open Settings/Plugins and install the Markdown plugin.
2. Turn off the preview function of Markdown files in Idea
Turn off Hide floating toolbar in Settings/Advance Settings
3. Not clearing the cache
Clear cache File/Invalidate Caches
4. JBR error, Jdk runtime error
Generally, after the cache is forcibly cleared, it is replaced with the default runtime.
Replace the runtime of the corresponding version, Ctrl + Shift + A to search for Java Runtime and choose to replace the runtime.
Linux input method patch runtime: https://github.com/RikudouPatrickstar/JetBrainsRuntime-for-Linux-x64
5. Confirm whether IntelliJ IDEA is associated with the .md file
Settings/Editor /File Types/Markdown/ Check whether the .markdown or .md file format is registered, if not, add .