title: $:/plugins/tiddlywiki/katex/developer

!! How to upgrade

# Download latest release zip file from [[Github release|https://github.com/KaTeX/KaTeX/releases]]
# Backup existing files
#* `plugins/tiddlywiki/katex/files/tiddlywiki.files` file and 
#* `katex.without-font-face.min.css` file
#* Learn more at: $:/plugins/tiddlywiki/katex/ImplementationNotes
# Rename extracted folder to "files" and 
#* copy it to `plugins/tiddlywiki/katex/files`
#* (maybe delete the old folder first, to make a full overwrite)
#* delete unused files in it, like `*.mjs` files and `*.md` files
# Create `plugins/tiddlywiki/katex/files/tiddlywiki.files`
#* (or use the old one) and 
#* register all needed files
# Register in `files/tiddlywiki.files`
#* `katex.without-font-face.min.css` ''as'' 
#* `$:/plugins/tiddlywiki/katex/katex.min.css`
#* so fonts are loaded properly in tw environment


!! How to test

To create a new "test edition" type the following command in a console window:

<<<
```
node tiddlywiki test-katex --init katexdemo
```
<<<

>It will create a new directory //test-katex// and clones the //katexdemo// edition.<br>The output should be:

<<<
`Copied edition 'katexdemo' to test-katex`
<<<

Type:

<<<
```
node tiddlywiki test-katex --listen
```
<<<

>It should output

<<<
`syncer-server-filesystem: Dispatching 'save' task: $:/StoryList
Serving on http://127.0.0.1:8080
(press ctrl-C to exit)
`
<<<

Test the new version in the browser at: [[http://127.0.0.1:8080]]

Make sure all equations of math and chemistry are rendered properly.