diff --git a/bundled-addons/pithos/addon.json b/bundled-addons/pithos/addon.json
index 34c95046..8ea5cc94 100644
--- a/bundled-addons/pithos/addon.json
+++ b/bundled-addons/pithos/addon.json
@@ -1,7 +1,7 @@
 {
   "id": "pithos",
   "name": "Pithos",
-  "version": "0.3.2",
+  "version": "0.3.3",
   "description": "Run s3d, the Sia S3 gateway, from the Theseus sidebar: connect it to a Sia indexer, create S3 users and access keys, browse and share buckets, and watch uploads reach Sia.",
   "author": "Silent Mode",
   "icon": "data:image/svg+xml;base64,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",
diff --git a/bundled-addons/pithos/core/s3.js b/bundled-addons/pithos/core/s3.js
index 8acaeda0..2153ab0e 100644
--- a/bundled-addons/pithos/core/s3.js
+++ b/bundled-addons/pithos/core/s3.js
@@ -14,9 +14,11 @@ const hmac = (k, s) => crypto.createHmac('sha256', k).update(s).digest();
 
 // RFC 3986 encoding as SigV4 wants it; '/' kept for object keys in paths.
 function uriEncode(str, keepSlash) {
-  return encodeURIComponent(str)
-    .replace(/[!'()*]/g, (c) => '%' + c.charCodeAt(0).toString(16).toUpperCase())
-    .replace(keepSlash ? /%2F/g : /$^/, '/');
+  const out = encodeURIComponent(str)
+    .replace(/[!'()*]/g, (c) => '%' + c.charCodeAt(0).toString(16).toUpperCase());
+  // (A "never matches" regex like /$^/ is not one: it matches the empty
+  // string, which turned every empty query value into "/".)
+  return keepSlash ? out.replace(/%2F/g, '/') : out;
 }
 
 function canonicalQuery(query) {