This article in a nutshell:
This post is all about how I updated my d12 Message Blocks plugin for WordPress.This is a message block.
Doing so meant learning how to add an options page to a WordPress plugin (simple), creating different styles and stylesheets to match (tedious), and rewriting the plugin’s `readme.text` file and creating a lot of new screenshots (easier, now that I’ve developed a workflow for it).
I really should write a press release for this on my techblog.
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https://iswpw.net/2015/10/17/updated-my-d12-message-blocks-plugin/