diff --git a/app/javascript/controllers/list_autofill_controller.js b/app/javascript/controllers/list_autofill_controller.js
index 74e827e9d..d69026859 100644
--- a/app/javascript/controllers/list_autofill_controller.js
+++ b/app/javascript/controllers/list_autofill_controller.js
@@ -1,5 +1,15 @@
 import { Controller } from '@hotwired/stimulus'
 
+// document.execCommand is deprecated: return false instead of throwing when a
+// browser has dropped it, so that callers can fall back to setRangeText.
+function tryExecCommand(command, argument) {
+  try {
+    return document.execCommand(command, false, argument)
+  } catch {
+    return false
+  }
+}
+
 class ListAutofillHandler {
   constructor(inputElement, format) {
     this.input = inputElement
@@ -36,7 +46,7 @@ class ListAutofillHandler {
         // Use execCommand so the edit participates in the browser's undo
         // stack (setRangeText and value assignments are not undoable).
         this.input.setSelectionRange(lineStartPos, selectionStart)
-        if (!document.execCommand('delete')) {
+        if (!tryExecCommand('delete')) {
           this.input.setRangeText('', lineStartPos, selectionStart, 'start')
         }
         break
@@ -49,7 +59,7 @@ class ListAutofillHandler {
         const text = result.text
         this.input.addEventListener('input', (e) => {
           if (e.inputType !== 'insertLineBreak') return
-          if (!document.execCommand('insertText', false, text)) {
+          if (!tryExecCommand('insertText', text)) {
             const el = e.currentTarget
             const pos = el.selectionStart
             el.setRangeText(text, pos, pos, 'end')
diff --git a/test/system/list_autofill_test.rb b/test/system/list_autofill_test.rb
index 6eef8d056..e6a7cd96a 100644
--- a/test/system/list_autofill_test.rb
+++ b/test/system/list_autofill_test.rb
@@ -348,4 +348,79 @@ class ListAutofillSystemTest < ApplicationSystemTestCase
       end
     end
   end
+
+  def test_undo_after_autofill_reverts_everything
+    with_settings :text_formatting => 'textile' do
+      visit '/projects/ecookbook/issues/new'
+
+      within('form#issue-form') do
+        find('#issue_description').send_keys('* First item')
+        find('#issue_description').send_keys(:enter)
+        find('#issue_description').send_keys('Second item')
+        assert_equal("* First item\n* Second item", find('#issue_description').value)
+
+        assert_equal('', undo_states(find('#issue_description')).last)
+      end
+    end
+  end
+
+  def test_undo_after_marker_removal_restores_the_marker
+    with_settings :text_formatting => 'textile' do
+      visit '/projects/ecookbook/issues/new'
+
+      within('form#issue-form') do
+        find('#issue_description').send_keys('* First item')
+        find('#issue_description').send_keys(:enter)
+        find('#issue_description').send_keys(:enter)
+        assert_equal("* First item\n", find('#issue_description').value)
+
+        states = undo_states(find('#issue_description'))
+        assert_includes(states, "* First item\n* ")
+        assert_equal('', states.last)
+      end
+    end
+  end
+
+  def test_autofill_falls_back_when_exec_command_is_unusable
+    stubs = {
+      'missing'  => 'document.execCommand = undefined;',
+      'refusing' => 'document.execCommand = function() { return false; };',
+      'throwing' => 'document.execCommand = function() { throw new Error("removed"); };'
+    }
+
+    with_settings :text_formatting => 'textile' do
+      stubs.each do |name, stub|
+        visit '/projects/ecookbook/issues/new'
+        page.execute_script(stub)
+
+        find('#issue_description').send_keys('* First item')
+        find('#issue_description').send_keys(:enter)
+        assert_equal("* First item\n* ", find('#issue_description').value,
+                     "marker was not inserted with a #{name} execCommand")
+
+        find('#issue_description').send_keys(:enter)
+        assert_equal("* First item\n", find('#issue_description').value,
+                     "marker was not removed with a #{name} execCommand")
+      end
+    end
+  end
+
+  private
+
+  # The browser applies an undo asynchronously and groups entries its own way,
+  # so wait for each press to land and collect every value seen.
+  def undo_states(field, max: 20)
+    keys = [RUBY_PLATFORM.include?('darwin') ? :command : :control, 'z']
+    states = [field.value]
+    max.times do
+      field.send_keys(keys)
+      deadline = Process.clock_gettime(Process::CLOCK_MONOTONIC) + Capybara.default_max_wait_time
+      sleep 0.05 while field.value == states.last &&
+                       Process.clock_gettime(Process::CLOCK_MONOTONIC) < deadline
+      break if field.value == states.last
+
+      states << field.value
+    end
+    states
+  end
 end