updates to markdown processing to allow custom elements

src/render.ts

@@ -4,7 +4,7 @@ import { create_renderer } from './renderer';
 import { mark_ext } from './mark';
 import { section_ext } from './section';
 import { icon_ext } from './icon';
-import { sanitize_html } from './html-sanitize';
+import { CustomElementHandling, sanitize_html } from './html-sanitize';
 import { katex_block_ext, katex_inline_ext } from './katex';
 import { footnote_list_ext, footnote_ref_ext } from './footnotes';
 import { description_list_ext } from './description-list';
@@ -16,6 +16,7 @@ export interface MarkdownOptions {
 	inline?: boolean;
 	katex_macros?: Record<string, string>;
 	extensions?: MarkdownExtension[];
+	custom_elements?: CustomElementHandling;
 }
 
 export interface MarkdownExtension {
@@ -64,5 +65,5 @@ export async function render_markdown_to_html(markdown: string, options: Markdow
 			});
 		});
 
-	return sanitize_html(unsafe_html);
+	return sanitize_html(unsafe_html, options.custom_elements);
 }