[doc] Minor improvements

Closes #3518, Closes #3560

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,28 +1,29 @@
-## Please follow the guide below
+<!--
+# Please follow the guide below
 
 - You will be asked some questions, please read them **carefully** and answer honestly
-- Put an `x` into all the boxes [ ] relevant to your *pull request* (like that [x])
+- Put an `x` into all the boxes `[ ]` relevant to your *pull request* (like [x])
 - Use *Preview* tab to see how your *pull request* will actually look like
 
----
+-->
 
 ### Before submitting a *pull request* make sure you have:
 - [ ] At least skimmed through [contributing guidelines](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#developer-instructions) including [yt-dlp coding conventions](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#yt-dlp-coding-conventions)
 - [ ] [Searched](https://github.com/yt-dlp/yt-dlp/search?q=is%3Apr&type=Issues) the bugtracker for similar pull requests
-- [ ] Checked the code with [flake8](https://pypi.python.org/pypi/flake8)
+- [ ] Checked the code with [flake8](https://pypi.python.org/pypi/flake8) and [ran relevant tests](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#developer-instructions)
 
 ### In order to be accepted and merged into yt-dlp each piece of code must be in public domain or released under [Unlicense](http://unlicense.org/). Check one of the following options:
 - [ ] I am the original author of this code and I am willing to release it under [Unlicense](http://unlicense.org/)
 - [ ] I am not the original author of this code but it is in public domain or released under [Unlicense](http://unlicense.org/) (provide reliable evidence)
 
 ### What is the purpose of your *pull request*?
-- [ ] Bug fix
-- [ ] Improvement
-- [ ] New extractor
-- [ ] New feature
+- [ ] Fix or improvement to an extractor (Make sure to add/update tests)
+- [ ] New extractor ([Piracy websites will not be accepted](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#is-the-website-primarily-used-for-piracy))
+- [ ] Core bug fix/improvement
+- [ ] New feature (It is strongly [recommended to open an issue first](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#adding-new-feature-or-making-overarching-changes))
 
 ---
 
 ### Description of your *pull request* and other information
 
-Explanation of your *pull request* in arbitrary form goes here. Please make sure the description explains the purpose and effect of your *pull request* and is worded well enough to be understood. Provide as much context and examples as possible.
+Explanation of your *pull request* in arbitrary form goes here. Please **make sure the description explains the purpose and effect** of your *pull request* and is worded well enough to be understood. Provide as much **context and examples** as possible.