FEATURE: posts per page is configurable, so should be desktop slack

app/assets/javascripts/discourse/lib/capabilities.js

@@ -19,12 +19,15 @@ Discourse.Capabilities = Ember.Object.extend({
     // Touch devices get more slack due to inertia
     if (this.get('touch')) { return 1.5; }
 
+    var desktopSlack = parseFloat(Discourse.SiteSettings.desktop_post_slack_ratio,10);
+    desktopSlack = Math.max(desktopSlack,1);
+
     // Higher resolution devices (likely laptops/desktops) should get more slack because they
     // can handle the perf.
-    return this.get('highRes') ? 2.0 : 0.75;
+    return this.get('highRes') ? desktopSlack : 0.75;
 
   }.property('android', 'touch', 'highRes')
 
 });
 
-Discourse.Capabilities.reopenClass(Discourse.Singleton);
+Discourse.Capabilities.reopenClass(Discourse.Singleton);

config/locales/server.en.yml

@@ -682,6 +682,7 @@ en:
     track_external_right_clicks: "Track external links that are right clicked (eg: open in new tab) disabled by default because it rewrites URLs"
     topics_per_page: "How many topics loaded by default on the topics list page, and when loading more topics"
     posts_per_page: "How many posts loaded by default on a topic page, and when loading more posts"
+    desktop_post_slack_ratio: "Number of screens of posts rendered in the DOM on Desktop"
     site_contact_username: "Username for the author of automated private messages sent by the forum"
     send_welcome_message: "Do new users get a welcome private message?"
     suppress_reply_directly_below: "Don't show reply count on a post when there is a single reply directly below"

config/site_settings.yml

@@ -85,6 +85,9 @@ basic:
   posts_per_page:
     client: true
     default: 20
+  desktop_post_slack_ratio:
+    default: 2
+    client: true
   enable_badges:
     client: true
     default: false