I just installed the plugin from https://github.com/discourse/discourse-characters-required and I have 2 requests that I believe would make the plugin a bit better:
1 - Adding the same feature to the title would be valuable as well. Showing that there's also a minimum number of characters there is a must.2 - Once the user starts typing, the text could change from N characters required to N characters left (or remaining). Then if the person deletes the text again, it goes back to required. This one is just a small tweak to make the feature more consistent to what's happening at a given moment. Not a "must", just a tweak.
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