While Discourse is a JavaScript application, it can still be crawled by Google and other search engines.
Discourse is designed in such a way that the entire content can be crawled by bots with or without JavaScript.
We ship NOSCRIPT tag containing topic list and topic content.
Additionally old browsers with old JavaScript engines will fallback to a simple read-only view.
To view the JS disabled view, you can either install a plugin in Chrome/Firefox that disables JS or disable using these instructions.
Here is an example of how meta is rendered to Googlebot:
Note that when using the no JS rendering we include pagination.
