diff --git a/package-lock.json b/package-lock.json
index e2f788b..99ddee7 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1612,9 +1612,9 @@
       "integrity": "sha512-MufnRFz39aIhs9AMFisonjzTud1PK1bY+jcJLo6m2T9Uh8AqjD77w11eAAawmjUogoGOnipECq7e/1RClIKsxg=="
     },
     "preact-render-to-string": {
-      "version": "4.1.0",
-      "resolved": "https://registry.npmjs.org/preact-render-to-string/-/preact-render-to-string-4.1.0.tgz",
-      "integrity": "sha512-FlFBJRxo8z4cp6VsDmeYjIEx4ZK2clFJnKIvIj8K1IQCRm7ZgJ/SZ1+BotT86/Nc+V1pNtFabHoUi6gpjx5Pug==",
+      "version": "5.1.21",
+      "resolved": "https://registry.npmjs.org/preact-render-to-string/-/preact-render-to-string-5.1.21.tgz",
+      "integrity": "sha512-wbMtNU4JpfvbE04iCe7BZ1yLYN8i6NRrq+NhR0fUINjPXGu3ZIc4GM5ScOiwdIP1sPXv9SVETuud/tmQGMvdNQ==",
       "requires": {
         "pretty-format": "^3.8.0"
       }
diff --git a/package.json b/package.json
index 6e22f65..603cc2c 100644
--- a/package.json
+++ b/package.json
@@ -9,7 +9,7 @@
     "@begin/data": "^3.0.4",
     "esm": "^3.2.25",
     "preact": "~10.7.1",
-    "preact-render-to-string": "~4.1.0",
+    "preact-render-to-string": "~5.1.21",
     "rollup": "^2.70.2",
     "tap-spec": "^5.0.0",
     "tape": "^5.5.3"