FIX: more consistent filter from keyboard on select-box

app/assets/javascripts/discourse/components/select-box.js.es6

@@ -78,6 +78,10 @@ export default Ember.Component.extend({
       this.set("content", []);
     }
 
+    if (this.site.isMobileDevice) {
+      this.set("filterable", false);
+    }
+
     this.setProperties({
       componentId: this.elementId,
       filteredContent: []
@@ -193,6 +197,13 @@ export default Ember.Component.extend({
         this.$(".select-box-offscreen").blur();
         return false;
       }
+
+      if (keyCode >= 65 && keyCode <= 90) {
+        this.setProperties({expanded: true, focused: false});
+        Ember.run.schedule("afterRender", () => {
+          this.$(".filter-query").focus().val(String.fromCharCode(keyCode));
+        });
+      }
     });
 
     this.$(".select-box-offscreen").on("focusout.select-box", () => {
@@ -259,6 +270,7 @@ export default Ember.Component.extend({
   _bindTab() {
     $(document).on("keydown.select-box", (event) => {
       const keyCode = event.keyCode || event.which;
+
       if (keyCode === 9) {
         this.set("expanded", false);
       }

app/assets/javascripts/discourse/templates/components/select-box/select-box-filter.hbs

@@ -3,6 +3,10 @@
   class="filter-query"
   placeholder=filterPlaceholder
   key-up=onFilterChange
+  autocomplete="off"
+  autocorrect="off"
+  autocapitalize="off"
+  spellcheck=false
 }}
 
 {{#if filterIcon}}

app/assets/javascripts/discourse/templates/preferences/emails.hbs

@@ -2,7 +2,7 @@
   <label class="control-label">{{i18n 'user.email_settings'}}</label>
   <div class='controls controls-dropdown'>
     <label>{{i18n 'user.email_previous_replies.title'}}</label>
-    {{combo-box valueAttribute="value" content=previousRepliesOptions value=model.user_option.email_previous_replies}}
+    {{select-box idKey="value" textKey="name" content=previousRepliesOptions value=model.user_option.email_previous_replies}}
   </div>
   {{preference-checkbox labelKey="user.email_in_reply_to" checked=model.user_option.email_in_reply_to}}
   {{preference-checkbox labelKey="user.email_private_messages" checked=model.user_option.email_private_messages}}
@@ -25,7 +25,7 @@
     {{preference-checkbox labelKey="user.email_digests.title" disabled=model.user_option.mailing_list_mode checked=model.user_option.email_digests}}
     {{#if model.user_option.email_digests}}
       <div class='controls controls-dropdown'>
-        {{combo-box valueAttribute="value" content=digestFrequencies value=model.user_option.digest_after_minutes}}
+        {{select-box idKey="value" filterable=true textKey="name" content=digestFrequencies value=model.user_option.digest_after_minutes}}
       </div>
       {{preference-checkbox labelKey="user.include_tl0_in_digests" disabled=model.user_option.mailing_list_mode checked=model.user_option.include_tl0_in_digests}}
     {{/if}}