diff --git a/common/modules/addons.jsm b/common/modules/addons.jsm
index c1e4e335..fd608a6e 100644
--- a/common/modules/addons.jsm
+++ b/common/modules/addons.jsm
@@ -83,14 +83,14 @@ var actions = {
         name: "exte[nable]",
         description: "Enable an extension",
         action: function (addon) { addon.userDisabled = false; },
-        filter: function ({ item }) item.userDisabled,
+        filter: function (addon) addon.userDisabled,
         perm: "enable"
     },
     disable: {
         name: "extd[isable]",
         description: "Disable an extension",
         action: function (addon) { addon.userDisabled = true; },
-        filter: function ({ item }) !item.userDisabled,
+        filter: function (addon) !addon.userDisabled,
         perm: "disable"
     },
     options: {
@@ -103,7 +103,7 @@ var actions = {
             else
                 this.dactyl.open(addon.optionsURL, { from: "extoptions" });
         },
-        filter: function ({ item }) item.isActive && item.optionsURL
+        filter: function (addon) addon.isActive && addon.optionsURL
     },
     rehash: {
         name: "extr[ehash]",
@@ -117,8 +117,8 @@ var actions = {
             });
         },
         get filter() {
-            return function ({ item }) !item.userDisabled &&
-                !(item.operationsRequiringRestart & (AddonManager.OP_NEEDS_RESTART_ENABLE | AddonManager.OP_NEEDS_RESTART_DISABLE))
+            return function (addon) !addon.userDisabled &&
+                !(addon.operationsRequiringRestart & (AddonManager.OP_NEEDS_RESTART_ENABLE | AddonManager.OP_NEEDS_RESTART_DISABLE))
         },
         perm: "disable"
     },
@@ -412,7 +412,7 @@ var Addons = Module("addons", {
         // TODO: handle extension dependencies
         values(actions).forEach(function (command) {
             let perm = command.perm && AddonManager["PERM_CAN_" + command.perm.toUpperCase()];
-            function ok(addon) !perm || addon.permissions & perm;
+            function ok(addon) (!perm || addon.permissions & perm) && (!command.filter || command.filter(addon));
 
             commands.add(Array.concat(command.name),
                 command.description,
@@ -430,6 +430,7 @@ var Addons = Module("addons", {
                             dactyl.assert(list.some(ok), _("error.invalidOperation"));
                             list = list.filter(ok);
                         }
+                        dactyl.assert(list.every(ok));
                         if (command.actions)
                             command.actions(list, this.modules);
                         else
@@ -441,8 +442,6 @@ var Addons = Module("addons", {
                     completer: function (context, args) {
                         completion.addon(context, args["-types"]);
                         context.filters.push(function ({ item }) ok(item));
-                        if (command.filter)
-                            context.filters.push(command.filter);
                     },
                     literal: 0,
                     options: [
diff --git a/common/modules/buffer.jsm b/common/modules/buffer.jsm
index 4debeeba..c5491489 100644
--- a/common/modules/buffer.jsm
+++ b/common/modules/buffer.jsm
@@ -2280,12 +2280,12 @@ var Buffer = Module("Buffer", {
 
         options.add(["nextpattern"],
             "Patterns to use when guessing the next page in a document sequence",
-            "regexplist", UTF8(/'\bnext\b',^>$,^(>>|»)$,^(>|»),(>|»)$,'\bmore\b'/.source),
+            "regexplist", UTF8(/'^Next [>»]','^Next »','\bnext\b',^>$,^(>>|»)$,^(>|»),(>|»)$,'\bmore\b'/.source),
             { regexpFlags: "i" });
 
         options.add(["previouspattern"],
             "Patterns to use when guessing the previous page in a document sequence",
-            "regexplist", UTF8(/'\bprev|previous\b',^<$,^(<<|«)$,^(<|«),(<|«)$/.source),
+            "regexplist", UTF8(/'[<«] Prev$','« Prev$','\bprev(ious)\b',^<$,^(<<|«)$,^(<|«),(<|«)$/.source),
             { regexpFlags: "i" });
 
         options.add(["pageinfo", "pa"],