docs fixes and additions

README.md

@@ -132,7 +132,7 @@ Besides the classic pagination offered by the `pagy_nav` helpers, you can use a
 
 - [pagy_nav_js](http://ddnexus.github.io/pagy/extras/navs#javascript-navs): A faster and lighter classic looking UI, rendered on the client side with optional responsiveness:<br>![bootstrap_nav_js](docs/assets/images/bootstrap_nav_js-w.png)
 
-- [pagy_combo_nav_js](http://ddnexus.github.io/pagy/extras/navs#javascript-combo-navs): The fastest and lighest alternative UI that combines navigation and pagination info in a single compact element:<br>![bootstrap_combo_nav_js](docs/assets/images/bootstrap_combo_nav_js-w.png)
+- [pagy_combo_nav_js](http://ddnexus.github.io/pagy/extras/navs#javascript-combo-navs): The fastest and lightest alternative UI _(48x faster, 48x lighter and 2,270x more efficient than Kaminari)_ that combines navigation and pagination info in a single compact element:<br>![bootstrap_combo_nav_js](docs/assets/images/bootstrap_combo_nav_js-w.png)
 
 ## Resources
 

docs/extras.md

@@ -53,7 +53,9 @@ A few helpers use javascript, and they are clearly recognizable by the `js` suff
 
 If you use any of them you should load the [pagy.js](https://github.com/ddnexus/pagy/blob/master/lib/javascripts/pagy.js) file, and run `Pagy.init()` on window load and eventually on [AJAX-load](#using-ajax-with-javascript-enabled-helpers).
 
-**CAVEATS**: if you override any `*_js` helper, ensure to override/enforce the relative javascript function, even with a simple copy and paste. If the relation between the helper and the function changes in a next release (e.g. arguments, naming, etc.), your app will still work with your own overriding even without the need to update it.
+**CAVEATS**
+- If you override any `*_js` helper, ensure to override/enforce the relative javascript function, even with a simple copy and paste. If the relation between the helper and the function changes in a next release (e.g. arguments, naming, etc.), your app will still work with your own overriding even without the need to update it.
+- See also [Preventing crawlers to follow look-alike links](how-to.md#preventing-crawlers-to-follow-look-alike-links)
 
 ### Add the oj gem
 

docs/how-to.md

@@ -476,6 +476,17 @@ If you don't have strict requirements but still need to give the user total feed
 
 If your requirements allow to use the `countless` extra (minimal or automatic UI) you can save one query per page, and drastically boost efficiency eliminating the nav info and almost all the UI. Take a look at the examples in the [support extra](extras/support.md).
 
+## Preventing crawlers to follow look-alike links
+
+The `*_js` helpers come with a JSON tag including a string that looks like an `a` link tag. It's just a placeholder string used by `pagy.js` in order to create actual DOM elements links, but some crawlers are reportedly following it even if it is not a DOM element. That causes server side errors reported in your log.
+
+You may want to prevent that by adding the following to your `robots.txt` file:
+
+```
+User-agent: *
+Disallow: *__pagy_page__
+```
+
 ## Handling Pagy::OverflowError exceptions
 
 Pass an overflowing `:page` number and Pagy will raise a `Pagy::OverflowError` exception.