I’m not making it up, you know 
and I can’t do much with being told it should work I followed that guide to the letter on a new VM install with Ubuntu 22.04.
- Symlinking the plugin into the discourse/plugins/ subfolder and changing JS code in the plugin is not seen unless I do d/shutdown_dev; d/boot_dev, despite restarting d/rails s and d/ember-cli
- Copying the plugin into the discourse/plugins/ subfolder and changing JS code in the plugin is seen without doing d/shutdown_dev; d/boot_dev but only restarting d/rails s and d/ember-cli
Feel free to try the above. The plugin in question is discourse-math, changing code in assets/initializers/javascript/*.js (keep in mind that these particular plugin files are side-loaded, and not GET called by the browser directly; not sure if that makes a difference, I haven’t dug too deep yet into how Discourse works internally).
p.s. I know I need to refresh the browser (bypassing cache) … give me some credit.