#7960 Add support for Markdown footnote syntax

Gemfile

@@ -103,10 +103,11 @@ source "https://gems.diasporafoundation.org" do
 
   gem "rails-assets-highlightjs",                         "9.12.0"
   gem "rails-assets-markdown-it",                         "8.4.2"
-  gem "rails-assets-markdown-it-hashtag",                 "0.4.0"
   gem "rails-assets-markdown-it-diaspora-mention",        "1.2.0"
-  gem "rails-assets-markdown-it-sanitizer",               "0.4.3"
+  gem "rails-assets-markdown-it-footnote",                "3.0.3"
+  gem "rails-assets-markdown-it-hashtag",                 "0.4.0"
   gem "rails-assets-markdown-it--markdown-it-for-inline", "0.1.1"
+  gem "rails-assets-markdown-it-sanitizer",               "0.4.3"
   gem "rails-assets-markdown-it-sub",                     "1.0.0"
   gem "rails-assets-markdown-it-sup",                     "1.0.0"
 

Gemfile.lock

@@ -577,6 +577,7 @@ GEM
     rails-assets-markdown-it--markdown-it-for-inline (0.1.1)
     rails-assets-markdown-it (8.4.2)
     rails-assets-markdown-it-diaspora-mention (1.2.0)
+    rails-assets-markdown-it-footnote (3.0.3)
     rails-assets-markdown-it-hashtag (0.4.0)
     rails-assets-markdown-it-sanitizer (0.4.3)
     rails-assets-markdown-it-sub (1.0.0)
@@ -890,6 +891,7 @@ DEPENDENCIES
   rails-assets-markdown-it (= 8.4.2)!
   rails-assets-markdown-it--markdown-it-for-inline (= 0.1.1)!
   rails-assets-markdown-it-diaspora-mention (= 1.2.0)!
+  rails-assets-markdown-it-footnote (= 3.0.3)!
   rails-assets-markdown-it-hashtag (= 0.4.0)!
   rails-assets-markdown-it-sanitizer (= 0.4.3)!
   rails-assets-markdown-it-sub (= 1.0.0)!

app/assets/javascripts/app/helpers/text_formatter.js

@@ -16,6 +16,9 @@
       typographer: true
     });
 
+    var footnote = window.markdownitFootnote;
+    md.use(footnote);
+
     var inlinePlugin = window.markdownitForInline;
     md.use(inlinePlugin, "utf8_symbols", "text", function (tokens, idx) {
       tokens[idx].content = tokens[idx].content.replace(/<->/g, "↔")

app/assets/javascripts/main.js

@@ -23,6 +23,7 @@
 //= require markdown-it
 //= require markdown-it-diaspora-mention
 //= require markdown-it-for-inline
+//= require markdown-it-footnote
 //= require markdown-it-hashtag
 //= require markdown-it-sanitizer
 //= require markdown-it-sub