It would be nice to have CI processing PRs in this repo. This could provide a preview of submitted guidelines updates.
I think @asamalik was working on something like this for docs... But I don't know what is the state.
Note that you can easily get a reasonable in-browser preview using the asciidoctor browser extension as described in this project's README file. It's certainly not exactly what you would see if something was actually running antora but it's still quite useful.
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