Enables Markdig GitHub-style alert block parsing (as UseAlertBlocks() does), plus the
Obsidian-style extras that Markdig alone leaves as a plain blockquote: foldable alerts
(> [!NOTE]- starts collapsed, > [!NOTE]+ starts expanded) and custom titles
(> [!TIP] My title). Can be combined with Markdig's UseAlertBlocks() in either order.
Activate on the viewer with viewer.UseAlertBlocks().
public static MarkdownPipelineBuilder UseExtendedAlertBlocks(this MarkdownPipelineBuilder builder)