diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 001af2df..ac590079 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -50,7 +50,7 @@ You may find the [demo application](#the-demo-application) useful for developmen
 - If your PR fixes an issues, be sure to put "Fixes #nnn" in the description of the PR (where `nnn` is the issue number). Github will automatically close the issue when the PR is merged.
 - When the PR is submitted, check if GitHub Actions ran all the tests successfully, and didn't raise any issues.
 
-When you create or update a pull request, GitHub automatically runs tests that generate the screenshots in the [`README.md`](/README.md). If any of the screenshots change, GitHub will add an additional commit with the updated screenshots.
+When you create or update a pull request, GitHub automatically runs tests that generate the screenshots in the [`README.md`](/README.md). If any of the screenshots change, GitHub will add an additional commit to your branch, with the updated screenshots.
 
 Normally, the screenshots should _not_ change. If the screenshots changed, please review them _carefully_. Some clear reasons why you would want to keep the changed screenshots:
 
@@ -73,7 +73,7 @@ You can run the tests that generate the screenshots locally, but unless your env
 
 ```bash
 cd demo
-bundle exec rails test:all
+bundle exec rails test:all # or test:system
 ```
 
 The [Docker development environment](#using-docker-compose) appears to generate screenshots that are the same as what GitHub generates.
diff --git a/README.md b/README.md
index 00d2f4a9..efc18ed5 100644
--- a/README.md
+++ b/README.md
@@ -1586,6 +1586,7 @@ If you want to display a custom inline error for a specific attribute not repres
 ![Example 50](demo/doc/screenshots/bootstrap/readme/50_example.png "Example 50")
 ```erb
 <%= bootstrap_form_for @user_with_error do |f| %>
+  <input class="is-invalid" autocomplete="off" disabled type="hidden">
   <%= f.errors_on :email %>
 <% end %>
 ```
@@ -1594,15 +1595,19 @@ Which outputs:
 
 ```html
 <form accept-charset="UTF-8" action="/users" class="new_user" id="new_user" method="post">
+  <input autocomplete="off" class="is-invalid" disabled type="hidden">
   <div class="invalid-feedback">Email is invalid</div>
 </form>
 ```
 
+Note that the `invalid-feedback` `div` is hidden unless there is a preceding element under the same parent that has class `is-invalid`. For the examples, we've artificially added a hidden input.
+
 You can hide the attribute name like this:
 
 ![Example 51](demo/doc/screenshots/bootstrap/readme/51_example.png "Example 51")
 ```erb
 <%= bootstrap_form_for @user_with_error do |f| %>
+  <input class="is-invalid" autocomplete="off" disabled type="hidden">
   <%= f.errors_on :email, hide_attribute_name: true %>
 <% end %>
 ```
@@ -1611,6 +1616,7 @@ Which outputs:
 
 ```html
 <form accept-charset="UTF-8" action="/users" class="new_user" id="new_user" method="post">
+  <input autocomplete="off" class="is-invalid" disabled type="hidden">
   <div class="invalid-feedback">is invalid</div>
 </form>
 ```
@@ -1620,6 +1626,7 @@ You can also use a custom class for the wrapping div, like this:
 ![Example 52](demo/doc/screenshots/bootstrap/readme/52_example.png "Example 52")
 ```erb
 <%= bootstrap_form_for @user_with_error do |f| %>
+  <input class="is-invalid" autocomplete="off" disabled type="hidden">
   <%= f.errors_on :email, custom_class: 'custom-error' %>
 <% end %>
 ```
@@ -1628,10 +1635,13 @@ Which outputs:
 
 ```html
 <form accept-charset="UTF-8" action="/users" class="new_user" id="new_user" method="post">
+  <input autocomplete="off" class="is-invalid" disabled type="hidden">
   <div class="custom-error">Email is invalid</div>
 </form>
 ```
 
+Note that adding the custom class removes the default `invalid-feedback` class. If you still want the default `invalid-feedback` formatting, add it to your `custom_class`es.
+
 ## Required Fields
 
 A label that is associated with a required field is automatically annotated with
diff --git a/demo/doc/screenshots/bootstrap/readme/50_example.png b/demo/doc/screenshots/bootstrap/readme/50_example.png
index 128c12e3..a9b96cc0 100644
Binary files a/demo/doc/screenshots/bootstrap/readme/50_example.png and b/demo/doc/screenshots/bootstrap/readme/50_example.png differ
diff --git a/demo/doc/screenshots/bootstrap/readme/51_example.png b/demo/doc/screenshots/bootstrap/readme/51_example.png
index 128c12e3..537a63ca 100644
Binary files a/demo/doc/screenshots/bootstrap/readme/51_example.png and b/demo/doc/screenshots/bootstrap/readme/51_example.png differ