3 files changed, 40 insertions, 30 deletions

diff --git a/app/javascript/flavours/glitch/components/intersection_observer_article.js b/app/javascript/flavours/glitch/components/intersection_observer_article.js
index 8b06f9a8c..f7f6b0a53 100644
--- a/app/javascript/flavours/glitch/components/intersection_observer_article.js
+++ b/app/javascript/flavours/glitch/components/intersection_observer_article.js
@@ -1,15 +1,10 @@
 import React from 'react';
 import PropTypes from 'prop-types';
+import ImmutablePureComponent from 'react-immutable-pure-component';
 import scheduleIdleTask from 'flavours/glitch/util/schedule_idle_task';
 import getRectFromEntry from 'flavours/glitch/util/get_rect_from_entry';
-import { is } from 'immutable';
 
-// Diff these props in the "rendered" state
-const updateOnPropsForRendered = ['id', 'index', 'listLength'];
-// Diff these props in the "unrendered" state
-const updateOnPropsForUnrendered = ['id', 'index', 'listLength', 'cachedHeight'];
-
-export default class IntersectionObserverArticle extends React.Component {
+export default class IntersectionObserverArticle extends ImmutablePureComponent {
 
   static propTypes = {
     intersectionObserverWrapper: PropTypes.object.isRequired,
@@ -27,15 +22,18 @@ export default class IntersectionObserverArticle extends React.Component {
   }
 
   shouldComponentUpdate (nextProps, nextState) {
-    const isUnrendered = !this.state.isIntersecting && (this.state.isHidden || this.props.cachedHeight);
-    const willBeUnrendered = !nextState.isIntersecting && (nextState.isHidden || nextProps.cachedHeight);
-    if (!!isUnrendered !== !!willBeUnrendered) {
-      // If we're going from rendered to unrendered (or vice versa) then update
+    if (!nextState.isIntersecting && nextState.isHidden) {
+      // It's only if we're not intersecting (i.e. offscreen) and isHidden is true
+      // that either "isIntersecting" or "isHidden" matter, and then they're
+      // the only things that matter (and updated ARIA attributes).
+      return this.state.isIntersecting || !this.state.isHidden || nextProps.listLength !== this.props.listLength;
+    } else if (nextState.isIntersecting && !this.state.isIntersecting) {
+      // If we're going from a non-intersecting state to an intersecting state,
+      // (i.e. offscreen to onscreen), then we definitely need to re-render
       return true;
     }
-    // Otherwise, diff based on props
-    const propsToDiff = isUnrendered ? updateOnPropsForUnrendered : updateOnPropsForRendered;
-    return !propsToDiff.every(prop => is(nextProps[prop], this.props[prop]));
+    // Otherwise, diff based on "updateOnProps" and "updateOnStates"
+    return super.shouldComponentUpdate(nextProps, nextState);
   }
 
   componentDidMount () {
diff --git a/app/lib/feed_manager.rb b/app/lib/feed_manager.rb
index fe5ebfc36..c16b25635 100644
--- a/app/lib/feed_manager.rb
+++ b/app/lib/feed_manager.rb
@@ -178,22 +178,7 @@ class FeedManager
   end
 
   def keyword_filter?(status, receiver_id)
-    text_matcher = Glitch::KeywordMute.text_matcher_for(receiver_id)
-    tag_matcher  = Glitch::KeywordMute.tag_matcher_for(receiver_id)
-
-    should_filter   = text_matcher.matches?(status.text)
-    should_filter ||= text_matcher.matches?(status.spoiler_text)
-    should_filter ||= tag_matcher.matches?(status.tags)
-
-    if status.reblog?
-      reblog = status.reblog
-
-      should_filter ||= text_matcher.matches?(reblog.text)
-      should_filter ||= text_matcher.matches?(reblog.spoiler_text)
-      should_filter ||= tag_matcher.matches?(status.tags)
-    end
-
-    should_filter
+    Glitch::KeywordMuteHelper.new(receiver_id).matches?(status)
   end
 
   def filter_from_mentions?(status, receiver_id)
diff --git a/app/models/glitch/keyword_mute_helper.rb b/app/models/glitch/keyword_mute_helper.rb
new file mode 100644
index 000000000..6d067947f
--- /dev/null
+++ b/app/models/glitch/keyword_mute_helper.rb
@@ -0,0 +1,27 @@
+require 'html2text'
+
+class Glitch::KeywordMuteHelper
+  attr_reader :text_matcher
+  attr_reader :tag_matcher
+
+  def initialize(receiver_id)
+    @text_matcher   = Glitch::KeywordMute.text_matcher_for(receiver_id)
+    @tag_matcher    = Glitch::KeywordMute.tag_matcher_for(receiver_id)
+  end
+
+  def matches?(status)
+    matchers_match?(status) || (status.reblog? && matchers_match?(status.reblog))
+  end
+
+  private
+
+  def matchers_match?(status)
+    text_matcher.matches?(prepare_text(status.text)) ||
+      text_matcher.matches?(prepare_text(status.spoiler_text)) ||
+      tag_matcher.matches?(status.tags)
+  end
+
+  def prepare_text(text)
+    Html2Text.convert(text)
+  end
+end