[MFM] Fix title syntax parsing

src/mfm/parse/elements/title.ts

@@ -8,8 +8,8 @@ export type TextElementTitle = {
 	title: string
 };
 
-export default function(text: string) {
-	const match = text.match(/^(【|\[)(.+?)(】|])\n/);
+export default function(text: string, i: number) {
+	const match = i == 0 ? text.match(/^(【|\[)(.+?)(】|])\n/) : text.match(/^\n(【|\[)(.+?)(】|])\n/);
 	if (!match) return null;
 	const title = match[0];
 	return {

test/mfm.ts

@@ -230,6 +230,11 @@ describe('Text', () => {
 			assert.deepEqual(
 				{ type: 'title', content: '[yee]\n', title: 'yee'}
 			, tokens2[0]);
+
+			const tokens3 = analyze('a [a]\nb [b]\nc [c]');
+			assert.deepEqual(
+				{ type: 'text', content: 'a [a]\nb [b]\nc [c]' }
+			, tokens2[0]);
 		});
 	});