diff --git a/app/helpers/excerpt_helper.rb b/app/helpers/excerpt_helper.rb
index 9ae0d3274..b48986c26 100644
--- a/app/helpers/excerpt_helper.rb
+++ b/app/helpers/excerpt_helper.rb
@@ -2,9 +2,9 @@ module ExcerptHelper
   def format_excerpt(content, length: 200)
     return "" if content.blank?
 
-    text = content.to_plain_text
+    text = content.respond_to?(:to_plain_text) ? content.to_plain_text : content.to_s
     text = text.gsub(/^>\s*(.*)$/m, '> \1')
-    text = text.gsub(/^[-*]\s*(.*)$/m, '• \1')
+    text = text.gsub(/^\s*[-+]\s*(.*)$/m, '• \1')
     text = text.gsub(/^\d+\.\s*(.*)$/m) { |m| m }
     text = text.gsub(/\s+/, " ").strip
     text.truncate(length)
diff --git a/test/helpers/excerpt_helper_test.rb b/test/helpers/excerpt_helper_test.rb
new file mode 100644
index 000000000..ef685680b
--- /dev/null
+++ b/test/helpers/excerpt_helper_test.rb
@@ -0,0 +1,31 @@
+require "test_helper"
+
+class ExcerptHelperTest < ActionView::TestCase
+  test "quote" do
+    assert_excerpt("> Hello world", ">    Hello world")
+  end
+
+  test "ul" do
+    assert_excerpt("• Hello world", "-    Hello world")
+    assert_excerpt("• Hello world", "  -    Hello world")
+  end
+
+  test "ol" do
+    assert_excerpt("99. Hello world", "99. Hello world")
+  end
+
+  test "large spaces" do
+    assert_excerpt("Hello world", "   Hello    world     ")
+  end
+
+  test "long text" do
+    assert_excerpt("A"*197 + "...", "A"*1000)
+    assert_excerpt("A"*97 + "...", "A"*1000, length: 100)
+  end
+
+  private
+    def assert_excerpt(expected, content, ...)
+      assert_equal expected, format_excerpt(ActionText::Content.new(content), ...), "Excerpt of Action Text Content does not match"
+      assert_equal expected, format_excerpt(content, ...), "Excerpt of String does not match"
+    end
+end