diff --git a/src/plugin/updater.cr b/src/plugin/updater.cr
index 4b69826..e490940 100644
--- a/src/plugin/updater.cr
+++ b/src/plugin/updater.cr
@@ -49,7 +49,7 @@ class Plugin
                    "Pushing to download queue"
       jobs = matches.map { |ch|
         Queue::Job.new(
-          "#{plugin.info.id}-#{ch["id"]}",
+          "#{plugin.info.id}-#{Base64.encode ch["id"].as_s}",
           "", # manga_id
           ch["title"].as_s,
           sub.manga_title,
diff --git a/src/queue.cr b/src/queue.cr
index 381441b..dc15d36 100644
--- a/src/queue.cr
+++ b/src/queue.cr
@@ -70,7 +70,13 @@ class Queue
       ary = @id.split("-")
       if ary.size == 2
         @plugin_id = ary[0]
-        @plugin_chapter_id = ary[1]
+        # This begin-rescue block is for backward compatibility. In earlier
+        #   versions we didn't encode the chapter ID
+        @plugin_chapter_id = begin
+          Base64.decode_string ary[1]
+        rescue
+          ary[1]
+        end
       end
     end
 
diff --git a/src/routes/api.cr b/src/routes/api.cr
index 4489f85..47e5558 100644
--- a/src/routes/api.cr
+++ b/src/routes/api.cr
@@ -785,7 +785,7 @@ struct APIRouter
 
         jobs = chapters.map { |ch|
           Queue::Job.new(
-            "#{plugin.info.id}-#{ch["id"]}",
+            "#{plugin.info.id}-#{Base64.encode ch["id"].as_s}",
             "", # manga_id
             ch["title"].as_s,
             manga_title,