Add note about link format

Avoid use of <link>

external/contribute/markdown/markdown.md

@@ -57,7 +57,7 @@ Markdown is a lightweight markup language with plain text formatting syntax whic
 |: ^^     + Indented item            | ^^      + Indented item
 |: ^^* Fourth item</pre>             | ^^ * Fourth item
 |:-----------------------------------|---------------------------|
-|: <pre>Include links referring to a web [page](https://www.markdownguide.org/)</pre> | Include links referring to a web [page](https://www.markdownguide.org/)
+|: Include links referring to a web `[page](https://www.markdownguide.org/)`. Avoid links in format `<link>` as it is not always parsed correctly. | Include links referring to a web [page](https://www.markdownguide.org/). Avoid links in format <link> as it is not always parsed correctly (like in this case).
 |:-----------------------------------|---------------------------|
 |: Include local pictures using markdown |
 |: ^^<pre>![My awesome picture](img/r3_logo.png)</pre> | ^^ ![My awesome picture](img/r3_logo.png)