From 74c823d50061b5ca1b3e4e2225dd83481f966d40 Mon Sep 17 00:00:00 2001
From: KMY <tt@kmycode.net>
Date: Sat, 4 Mar 2023 21:15:22 +0900
Subject: [PATCH 1/4] Add superscript/strikethrough flags on markdown

---
 app/javascript/styles/mastodon/rich_text.scss | 4 ++++
 app/lib/text_formatter.rb                     | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/app/javascript/styles/mastodon/rich_text.scss b/app/javascript/styles/mastodon/rich_text.scss
index a8258ee8cb..334ba98425 100644
--- a/app/javascript/styles/mastodon/rich_text.scss
+++ b/app/javascript/styles/mastodon/rich_text.scss
@@ -87,6 +87,10 @@
     color: $ui-secondary-color;
     padding: 0 2px;
   }
+
+  sup {
+    vertical-align: super;
+  }
 }
 
 .reply-indicator__content {
diff --git a/app/lib/text_formatter.rb b/app/lib/text_formatter.rb
index 607583ab2f..93c21e6029 100644
--- a/app/lib/text_formatter.rb
+++ b/app/lib/text_formatter.rb
@@ -174,6 +174,8 @@ class TextFormatter
         underline: true,
         disable_indented_code_blocks: false,
         fenced_code_blocks: true,
+        strikethrough: true,
+        superscript: true,
         highlight: false
       )
     @markdown.render(html)

From d014ffd6d03bfbaa5a463661d01bd68de49629cd Mon Sep 17 00:00:00 2001
From: KMY <tt@kmycode.net>
Date: Sun, 5 Mar 2023 08:06:46 +0900
Subject: [PATCH 2/4] Remove underline markdown

---
 app/lib/text_formatter.rb | 1 -
 1 file changed, 1 deletion(-)

diff --git a/app/lib/text_formatter.rb b/app/lib/text_formatter.rb
index 93c21e6029..0f748cd41c 100644
--- a/app/lib/text_formatter.rb
+++ b/app/lib/text_formatter.rb
@@ -171,7 +171,6 @@ class TextFormatter
     @markdown ||= Redcarpet::Markdown.new(@htmlobj,
         autolink: false,
         tables: false,
-        underline: true,
         disable_indented_code_blocks: false,
         fenced_code_blocks: true,
         strikethrough: true,

From 7c7d21cbefa36cfa9c97712f1a693d91196c0ee2 Mon Sep 17 00:00:00 2001
From: KMY <tt@kmycode.net>
Date: Sun, 5 Mar 2023 08:15:33 +0900
Subject: [PATCH 3/4] Fix underline

---
 app/lib/text_formatter.rb | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/app/lib/text_formatter.rb b/app/lib/text_formatter.rb
index 0f748cd41c..f4a904c8af 100644
--- a/app/lib/text_formatter.rb
+++ b/app/lib/text_formatter.rb
@@ -175,6 +175,7 @@ class TextFormatter
         fenced_code_blocks: true,
         strikethrough: true,
         superscript: true,
+        underline: true,
         highlight: false
       )
     @markdown.render(html)
@@ -197,6 +198,10 @@ class TextFormatter
       "<p>#{text}</p>"
     end
 
+    def underline(text)
+      nil
+    end
+
     private
 
     def process_program_code(code)

From b049e7c502d2531163a5ae80912d0bd91a0de929 Mon Sep 17 00:00:00 2001
From: KMY <tt@kmycode.net>
Date: Sun, 5 Mar 2023 09:05:16 +0900
Subject: [PATCH 4/4] Fix markdown underline with custom emoji

---
 app/lib/text_formatter.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/app/lib/text_formatter.rb b/app/lib/text_formatter.rb
index f4a904c8af..91c0ac1273 100644
--- a/app/lib/text_formatter.rb
+++ b/app/lib/text_formatter.rb
@@ -199,7 +199,7 @@ class TextFormatter
     end
 
     def underline(text)
-      nil
+      text.include?(':') ? nil : '<u>' + text + '</u>'
     end
 
     private